Virtual and physical dental models of dental surfaces and analog socket structure of a dental implant and related procedures

ABSTRACT

A system and method are provided for manufacturing a physical model of a dental structure that includes a dental implant. In at least one example, the physical model is configured to allow a dental analog can be inserted into the physical model in a general coronal direction. A virtual model of the dental structure is provided including a virtual implant spatial disposition with respect to the virtual model corresponding to a physical implant spatial disposition of the dental implant with respect to the physical dental structure. A virtual analog installation structure is defined in the virtual model. Using the virtual model, a physical model corresponding to the virtual model is manufactured, the physical model being provided with a physical analog installation structure corresponding to the virtual analog installation structure. The physical analog installation structure is configured for enabling a dental analog, corresponding to the dental implant, to be inserted in a general coronal direction with respect to the physical model to an installed position in the physical model. In the installed position, the dental analog has an analog spatial disposition with respect to the physical model corresponding to the physical implant spatial disposition of the dental implant with respect to the physical dental structure. A composite physical model, and methods for manufacturing the same, are also provided.

CROSS-REFERENCE

This application is a continuation application of U.S. application Ser.No. 15/673,211, filed Aug. 9, 2017, which is a continuation applicationof U.S. application Ser. No. 13/876,436, filed Mar. 27, 2013, now U.S.Pat. No. 9,763,758, issued Sep. 19, 2017, which is a U.S. National PhaseApplication under 35 U.S.C. § 371 of International Application No.PCT/IL2012/050011, filed Jan. 12, 2012, which claims priority to U.S.Provisional Application No. 61/432,247, filed Jan. 13, 2011, entitled“METHODS, SYSTEMS AND ACCESSORIES USEFUL FOR PROCEDURES RELATING TODENTAL IMPLANTS,” each of which are incorporated herein by reference intheir entirety.

FIELD OF THE INVENTION

The presently disclosed subject matter relates to dental implants and todental models, in particular to methods, systems and accessories usefulin procedures relating to dental implants. In particular, the presentlydisclosed subject matter relates to methods, systems and accessories forpreparing a physical dental model for use with an analog of a dentalimplant, to physical models prepared in this manner, and to dentalanalogs for use with such physical models.

BACKGROUND

Dental implants are widely used as artificial substitutes for the rootportion of missing teeth, and allow a tooth prosthesis to be securelyanchored to the jaw, for example via a permanent abutment mounted to theimplant. Endosseous implants generally comprise an externally threadedbody, often self-taping into the bone tissues, and further comprise aninternal chamber that is configured, typically internally threaded, forreceiving and securing therein the anchoring stem of a permanentabutment therein.

Also well known in the art are dental analogs, each of which is areplica of a corresponding dental implant. A dental analog has aninternal passage and an interface structure that are respectivelyidentical to the internal passage and interface structure of the implantthat is designed to receive, engage and secure the prosthesis andpermanent abutment; however, in contrast to the dental implant, thedental analog is not intended for implantation in a human, but ratherfor use with a physical model of the intraoral cavity or part thereof.

Conventionally, following implantation of a dental implant in the intraoral cavity and healing of the surrounding tissues, a physical model ofthe intra oral cavity is often produced for facilitating design andmanufacture of the permanent abutment and the prosthesis or otherrestoration that is to be eventually mounted onto the implant. In oneprocedure, an impression abutment is mounted to the implant so that itprojects into the intra oral cavity, and an impression is then obtainedof the intraoral cavity using well known techniques (for example, as areknown in the art regarding fixture level impressions) and impressionmaterials, for example PVS. The impression abutment can be of thepick-up type, to be embedded with the impression material and retainedtherein after the impression tray is removed. Alternatively theimpression tray is removed without the impression abutment attachedthereto, but nevertheless having a recess formed therein complementaryto the outer shape of the impression abutment, enabling thetransfer-type impression abutment to be mounted therein at a later time.Subsequently an analog, corresponding to the particular implant that isimplanted in the patient, is attached to the impression abutment, whichis in situ in the impression material, and plaster is poured into theimpression tray including the analog to produce a positive plaster modelof the intraoral cavity with the analog embedded. The analog is in aspatial disposition, i.e., at a position and orientation, in the plastermodel corresponding to the spatial disposition of the implant in thepatient's intra oral cavity. The dental technician can now attach apermanent abutment, or custom design a permanent abutment to fit theimplant, and build a coping or bridge framework or prosthesis to fitinto the intraoral cavity of the patient.

US 2010/0021859, assigned to the present Assignee, discloses a methodand system for manufacturing a physical dental model. A virtual model isprovided representative of at least a portion of the intra-oral cavityincluding at least one dental implant implanted therein, and the virtualmodel includes a virtual portion representative of each dental implant.A physical model is then manufactured based on the virtual model, thephysical model including a physical analog corresponding to each implantat a respective physical spatial disposition with respect to thephysical model corresponding to the respective virtual spatialdisposition of the respective virtual portion with respect to the firstvirtual model.

By way of general background, the following publications relate toimplants, analogs or to dental procedures relating to dental implants oranalogs: U.S. Pat. No. 6,358,052, US 2010/0112527, US 2008/032262, US2007/0092854, US 2006/183078, US 2003/0162148, WO 2010/108919, US2011/294093.

Herein the “the coronal direction” with respect to a tooth refers to thedirection originating from the region of the tooth root below the jawtowards the region of the crown above the jaw, while “the apicaldirection”, refers to the direction opposite to the coronal direction.

SUMMARY

Herein “operating on” with respect to a virtual entity, for example avirtual model of the dental structure, a virtual analog installationstructure, and so on, refers to conducting one or more of the followingoperations on the virtual entity with respect to any spatial coordinatesystem: translating, rotating, scaling, transforming, modifying, addingspatial data (for example adding virtual components), subtractingspatial data (for example removing, deleting or replacing virtualcomponents).

According to a first aspect of the presently disclosed subject matter asystem and a method are provided for manufacturing a physical model of adental structure that includes a dental implant, in which a dentalanalog can be inserted into the physical model in a general coronaldirection.

According to the first aspect of the presently disclosed subject matterthere is also provided a method for creating a virtual model usable formaking a physical model of a physical dental structure that includes adental implant at an implant site, the method comprising:

using a computer system:

-   -   (a) receiving a virtual representation of dental surfaces of the        physical dental structure with dental implant data representing        a location and orientation of the dental implant with respect to        the dental surfaces;    -   (b) receiving a virtual analog structure, the virtual analog        structure being based on said dental implant; and    -   (c) creating the virtual model based on:        -   said virtual representation of dental surfaces; and        -   a virtual analog socket structure based on said virtual            analog structure and said dental implant data, and having an            virtual analog insertion opening that is spaced from parts            of the virtual model corresponding to dental surfaces and            the implant site.

According to this aspect of the presently disclosed subject matter thereis also provided a method for manufacturing a physical model of aphysical dental structure that includes dental surfaces and a dentalimplant at an implant site, for use with a dental analog correspondingto the dental implant, the method comprising:

-   -   receiving a virtual model of the physical dental structure and a        virtual analog installation structure in association with said        virtual model, said virtual analog installation structure being        based on the dental analog;    -   using said virtual model, manufacturing a physical model        corresponding to said virtual model, the physical model being        provided with an analog installation structure based on said        virtual analog installation structure and thereby configured for        enabling the dental analog to be inserted into said physical        model through an insertion opening,    -   wherein said insertion opening is spaced from a location in the        physical model corresponding to the implant site in the physical        dental structure.

According to this aspect of the presently disclosed subject matter thereis also provided a physical model of a dental structure, the dentalstructure including a dental implant at an implant site, the physicalmodel being configured for enabling insertion therein of a dental analogcorresponding to the dental implant via an insertion opening that isspaced from a model implant site location on the physical modelcorresponding to the implant site.

According to this aspect of the presently disclosed subject matter thereis also provided a dental analog configured for being inserted into apassageway of a physical model of a dental structure, which dentalstructure includes a dental implant at an implant site, the passagewayincluding an insertion opening and a second opening corresponding to theimplant site, said second opening having a smaller maximum width than amaximum width of said insertion opening. For example, the dental analogcomprises a first analog end corresponding to said insertion opening anda second analog end corresponding to said second opening, wherein saidsecond analog end has a smaller maximum width than a maximum width ofsaid first analog end.

According to the first aspect of the presently disclosed subject mattera system and a method are provided for manufacturing a physical model ofa dental structure that includes a dental implant, in which the physicalmodel comprises a dental surface portion representative of the dentalsurfaces of the dental structure and a base portion, the physical modelbeing configured for enabling insertion of a dental analog into thephysical model via the base portion. According to the first aspect ofthe presently disclosed subject matter there is also provided a physicalmodel of a dental structure that includes a dental implant, the physicalmodel comprising a dental surface portion representative of the dentalsurfaces of the dental structure and a base portion, and the physicalmodel being configured for enabling insertion of a dental analog intothe physical model via the base portion.

According to a second aspect of the presently disclosed subject matterthere is provided a system and method for manufacturing a compositephysical dental model of a dental structure, the method comprising:

-   -   (a) providing a virtual model of the dental structure;    -   (b) using said virtual model, manufacturing a composite physical        model corresponding to said virtual model, the physical model        including a first model part and a second model part having at        least one physical property different from a physical property        of said first model part, wherein said first model part and said        second model part are previously defined in said virtual model,        and wherein said at least one physical property excludes a        surface topology.

A feature of at least one example according to the first aspect and/orsecond aspect of the presently disclosed subject matter is that theinsertion path of the physical analog is substantially independent ofthe topology of the dental surfaces in the vicinity of the implant site.This can facilitate installation of the respective analog for example incases where trying to insert the analog in the physical model in anapical direction would be difficult or impossible because of potentialcollision with surrounding dental structures, for example, where therespective dental implant is at an awkward or shallow angle with respectto the gums and the surrounding teeth.

Another feature of at least one example according to the first aspectand/or second aspect of the presently disclosed subject matter is thatthe physical model in the vicinity of the opening around the analog canbe defined with relatively high accuracy, since the method ofinstallation of the analog does not require any surface detail in thispart of the physical model to be disturbed, which can sometimes be thecase if the analog were to be installed instead in the physical model inan apical direction.

In at least one example the physical model thus prepared according tothe first aspect and/or second aspect of the presently disclosed subjectmatter can assist the dental technician in the design and/or preparationof the permanent abutment, coping, prosthesis and so on, in a mannerknown in the art. Such a prosthesis can include, for example, a customabutment and a crown, a custom abutment and a bridge, a complete crownmounted directly to the implant, a complete bridge mounted directly tothe implant, a denture, or a partial denture.

Optionally, the physical model or the composite model can be configuredfor mounting onto any dental articulator.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to understand the presently disclosed subject matter and to seehow it may be carried out in practice, examples will now be described,by way of non-limiting example only, with reference to the accompanyingdrawings, in which:

FIG. 1 illustrates in cross-sectional side view a dental structureincluding an example of a dental implant implanted therein in the placeof a removed tooth; FIG. 1(a) illustrates in exploded view an example ofprosthesis set including an abutment, prosthesis and retainer screw forthe example of the dental implant of FIG. 1.

FIG. 2 schematically illustrates an example of a general coronaldirection with respect to a spatial coordinate system referenced to theremoved tooth and dental structure of FIG. 1.

FIG. 3 is a schematic illustration of an example of a system accordingto a first aspect of the presently disclosed subject matter.

FIG. 4 is a schematic illustration of an example of a method accordingto a first aspect of the presently disclosed subject matter; FIG. 4(a)is a schematic illustration of an example of step 450 of FIG. 4; FIG.4(b) is a schematic illustration of a variation of the example of FIG.4; FIG. 4(c) is a schematic illustration of an example of a method forcreating a virtual model according to a first aspect of the presentlydisclosed subject matter.

FIG. 5 illustrates in cross-sectional side view an example of a dentalmodel corresponding to the dental structure of FIG. 1 and including acorresponding example of a dental analog inserted therein.

FIG. 6(a) illustrates in isometric view the dental analog example ofFIG. 5; FIGS. 6(b) to 6(d) respectively illustrate in isometric viewalternative variations of the dental analog example of FIG. 6(a); FIG.6(e) illustrates in cross-sectional side view the dental analog exampleof FIG. 6(a) used in a variation of the example of a physical model ofFIG. 5; FIG. 6(f) illustrates in cross-sectional side view anothervariation of the dental analog example of FIG. 6(a) inserted intoanother variation of the example of the physical model of FIG. 5; FIG.6(g) illustrates in cross-sectional side view another variation of thedental analog example of FIG. 6(a) inserted into another variation ofthe example of the physical model of FIG. 5; FIG. 6(h) illustrates incross-sectional side view another variation of the dental analog exampleof FIG. 6(a) inserted into another variation of the example of thephysical model of FIG. 5; FIG. 6(i) illustrates in cross-sectional frontview another variation of the dental analog example of FIG. 6(a)inserted into another variation of the example of the physical model ofFIG. 5.

FIG. 7 illustrates in cross-sectional side view another example of adental model corresponding to the dental structure of FIG. 1 andincluding a corresponding example of a dental analog inserted therein.

FIG. 8 illustrates in cross-sectional side view another example of adental model corresponding to the dental structure of FIG. 1 andincluding a corresponding example of a dental analog inserted therein;FIG. 8(a) illustrates in isometric view the dental analog example ofFIG. 8; FIG. 8(b) illustrates in isometric view a variation of thedental analog example of FIG. 8(a).

FIG. 9 illustrates in cross-sectional side view another example of adental model corresponding to the dental structure of FIG. 1 andincluding a corresponding example of a dental analog inserted therein.

FIG. 10 illustrates in cross-sectional side view an example of a virtualmodel corresponding to the physical dental model of FIG. 5 and includinga corresponding example of a virtual dental analog virtually insertedtherein.

FIG. 11 illustrates in cross-sectional side view another example of adental model corresponding to the dental structure of FIG. 1 andincluding a corresponding example of a dental analog inserted therein.

FIG. 12 illustrates in cross-sectional side view another example of adental model corresponding to the dental structure of FIG. 1 andincluding a corresponding example of a dental analog inserted thereinusing a jig.

FIG. 13 is a schematic illustration of an example of a method accordingto a second aspect of the presently disclosed subject matter; FIG. 13(a)is a schematic illustration of an example of step 950 of FIG. 11.

FIGS. 14(a) to 14(c) illustrate in side view a number of stagesassociated with providing a composite physical model example accordingto the second aspect of the presently disclosed subject matter; FIG.14(a) illustrates in cross-sectional side view a virtual model exampleaccording to this aspect of the presently disclosed subject matter; FIG.14(b) separately illustrates in cross-sectional side view a hard partand a soft part of composite physical model corresponding to the virtualmodel example of FIG. 14(a); FIG. 14(c) illustrates in cross-sectionalside view the example of FIG. 14(b) with the soft part engaged with thehard part of the composite physical model example, and with the analogof the example of FIG. 6(a) accommodated at the installed position inthe composite physical model example.

DETAILED DESCRIPTION

According to a first aspect of the presently disclosed subject matterthere is provided a system and method for use in dental implantprocedures, in particular for designing and manufacturing a physicaldental model (also referred to interchangeably herein as a physicalmodel) of a dental structure, based on and corresponding to a virtualdental model (also referred to interchangeably herein as a virtualmodel) of the dental structure.

Referring to FIG. 1, there is illustrated an example of such a dentalstructure, designated in this figure with the reference numeral 100. Thedental structure 100 is part of the intra-oral cavity of a patient, inparticular a visually exposed part of the intra-oral cavity of thepatient, and can include partial or the full mandibular or maxillaryarches, or both arches. Furthermore, the dental structure 100 includes adental implant 240 implanted therein at a particular implant site 150,and which replaces, in part, a tooth T (FIG. 2) that was previouslyremoved. The dental structure 100 comprises dental surfaces 115,including hard dental surfaces 110 and soft dental surfaces 120 thereof.Such hard surfaces 110 can include, for example, teeth and/or dentalprostheses that are mounted to the intra-oral cavity of the patient inthe vicinity of the dental implant site 150, while such soft dentalsurfaces 120 can include the gum, for example gingival surfaces thatsurround the implant. As will become clearer herein, the term “dentalstructure” can also refer, mutatis mutandis, to an existing physicalmodel of the aforesaid part of the intra-oral cavity of the patient, inwhich a portion of the existing physical model is shaped to representthe exposed surfaces of the dental implant that is implanted in theintra-oral cavity of the patient. For example, such an existing physicalmodel can be produced using conventional impression and castingtechniques, which are well known in the art. In such an example of thedental structure 100 in the form of an existing physical model, the harddental surfaces 110 and soft dental surfaces 120 thereof are surfaces ofthe existing physical model that represent the respective hard dentalsurfaces and soft dental surfaces of the intraoral cavity of thepatient.

Referring again to FIG. 1, the dental implant 240 is illustrated in theimplanted position with respect to the dental structure 100, i.e., at aparticular and fixed spatial disposition P with respect to dentalstructure 100.

Herein, by spatial disposition P is meant the orientation and thespatial position, or the orientation and the spatial location, in 3Dspace of the dental implant 240 with respect to the dental structure100, in particular with respect to some or all of the dental surfaces115.

The dental implant 240 can comprise any suitable implant configurationthat is commercially available or alternatively that is custom made. Thedental implant 240 in this example comprises a prosthesis interfaceimplant part 248 and a prosthesis engaging implant part 241, and isengaged to the dental structure 100 via an anchoring structure such asexternal screw threads 242. For example, prosthesis interface implantpart 248 can comprise a hexagonal counter-bored configuration and theprosthesis engaging implant part 241 can comprise an internally threadedwell, compatible with many types of commercially available prostheses;other configurations for these components can of course be comprised,instead, in the dental implant. For example the dental implant cancomprise a Morse taper connection; and/or can be configured for use witha screw retained crown or a cemented crown; and/or can be configured forstraight or angulated abutments.

Referring to FIG. 1(a), an example of a prosthesis system 991 isillustrated for use with dental implant 240. In this example, theprosthesis system 991 includes a dental prosthesis 990 that can bemounted to the dental implant 240 via a permanent abutment 995 andretainer screw 996. The prosthesis interface implant part 248 and theprosthesis engaging implant part 241 mate with and engage to acomplementary structure in the dental prosthesis 990 and/or permanentabutment 995.

While the following examples are each directed to a case of a singleimplant implanted in the dental structure, it is readily appreciatedthat the system and method are readily applicable in a similar manner,mutatis mutandis, to cases in which there is a plurality of implantsthat can be implanted in the intraoral cavity of a patient, whether theimplants are independent from one another, each being used for aseparate prosthesis, or whether at least some of the implants are to becoupled to be used together for a single bridge prosthesis or othermultiple tooth prostheses, dentures, etc., for example.

As will become readily apparent, corresponding to the dental structure100, a physical dental model is manufactured according to the firstaspect of the presently disclosed subject matter including physicalmodel surfaces that are representative of at least some of the harddental surfaces 110 and soft dental surfaces 120 of the dental structure100.

As will also become readily apparent, in at least some examples of thephysical model, the physical model includes a passageway having ananalog insertion opening in the physical model, for example at a basethereof. The passageway and analog insertion opening are configured toallow a dental analog, corresponding to the dental implant, to beinstalled into the physical model in an insertion path along aninsertion direction, to an installed position in the model.

In at least some examples, the insertion direction is referred to hereinas the respective general coronal direction K, as defined below, and isfixed for a particular set of: (a) a physical model and (b) the form ordesign of the corresponding analog. Referring again to FIG. 1, in somecases, where the dental implant is implanted having its axis AI parallelor close to the coronal direction CO, the insertion direction for thecorresponding implant, i.e., the respective general coronal direction,can also be parallel or near parallel to coronal direction CO. On theother hand, there are specific cases where the implant has beenimplanted in a spatial disposition with respect to the dental structurewhere the axis AI is inclined at a relatively large acute angle to thecoronal direction CO. In such cases, and depending on the design of thedental implant, the insertion direction for the implant, i.e., therespective general coronal direction, can also be relatively large acuteangle to coronal direction CO.

In the installed position, the analog is coupled to the physical modelin a relative spatial disposition (i.e., at a spatial position/locationand orientation in 3D space) with respect to the physical model thatcorresponds to and replicates the relative spatial disposition betweenthe dental implant and the dental structure. As will become readilyapparent, the passageway is first modeled in the corresponding virtualdental model of the dental structure, which in turn enables the physicalpassageway in the physical model to be manufactured.

Referring to FIG. 2, an example of a general coronal direction K isillustrated with respect to six directions along three orthogonal axesx, y, z of a spatial coordinate system. The spatial coordinate systemis, in this example, Cartesian coordinate system XYZ, and is referencedto the removed tooth T and with respect to the original location oftooth T in the dental structure 100. The aforesaid six directionsinclude: the true coronal direction CO and the true apical direction APthe removed tooth T, along the z-axis; the mesial direction ME and thedistal direction DI the removed tooth T, along the x-axis; and thebuccal direction BU and the lingual direction LI the removed tooth T,along the y-axis.

The “true coronal direction”, used herein synonymously with “the coronaldirection”, refers to the direction originating from the region of thetooth root within the jaw and extending towards the region of the crownabove the jaw, with reference to the tooth T and with respect to theoriginal location of tooth T in the dental structure 100, at or near thecurrent implant site 150. Since teeth are sometimes crooked, the truecoronal direction CO (and thus the orientation of the respectiveCartesian coordinate system XYZ) relative to the jaw can vary betweenone tooth and another in the same jaw. The “true apical direction”, usedherein synonymously with “the apical direction”, refers to the directionopposite to the true coronal direction.

A mesial-buccal plane MB can be defined, aligned with the mesialdirection ME and the distal direction DI on the one hand, and the buccaldirection BU and lingual direction LI on the other hand, i.e., the x-yplane.

Similarly, a coronal-buccal plane CB can be defined, aligned with thetrue coronal direction CO and true apical direction AP on the one hand,and the buccal direction BU and lingual direction LI on the other hand,i.e., the z-y plane.

Similarly, a coronal-mesial plane CM can be defined, aligned with thetrue coronal direction CO and true apical direction AP on the one hand,and the mesial direction ME and distal direction DI on the other hand,i.e., the z-x plane.

It is to be noted that by “general coronal direction” K is meant anydirection having a directional vector that can be angularly displacedfrom the true coronal direction CO in 3D space by a total angulardisplacement with respect to the true coronal direction CO not greaterthan 90°. The term “general coronal direction” thus includes anydirection having a directional vector including at least one directionalcomponent thereof aligned with true coronal direction CO. Additionallyor alternatively, “general coronal direction” is meant any directionhaving a directional vector that excludes having any directionalcomponent thereof aligned with true apical direction AP, i.e., along anon-apical direction.

The aforesaid total angular displacement, designated as angle θ in FIG.2, can have a first angular component, angle α, and/or a second angularcomponent, angle β.

For example, the first angular component, angle α, can be defined as theangular disposition of a first projection K1 of the general coronaldirection K on the coronal-mesial plane CM, taken with respect to thetrue coronal direction CO and towards the meisal direction ME (orinstead taken with respect to the true coronal direction CO and towardsthe distal direction DI).

For example, the second angular component, angle β, can be defined asthe angular disposition of a second projection K2 of the general coronaldirection K on the coronal-buccal plane CB, taken with respect to thetrue coronal direction CO and towards the lingual direction LI (orinstead taken with respect to the true coronal direction CO and towardsthe buccal direction BU).

Alternatively, one or the other of the first angular component and thesecond angular component can be replaced with a third angular component,angle ϕ. Angle ϕ can be defined as the angular disposition of a thirdprojection K3 of the general coronal direction K on the mesial-buccalplane MB, taken with respect to the meisal direction ME and towards thelingual direction LE (or towards the buccal direction BU), or indeedtaken with respect to the distal direction DI and towards the lingualdirection LI or towards the buccal direction BU.

In at least one example, angle a can be zero, so that the generalcoronal direction K lies on the coronal-buccal plane CB. In at least oneexample angle β can be zero, so that the general coronal direction Klies on coronal-mesial plane CM. In at least one example, angle α andangle β can both be zero, so that the general coronal direction K isparallel or aligned with the true coronal direction CO.

It is readily apparent that the first angular component, angle α, andthe second angular component, angle β, can be defined on any desiredfirst and second different but mutually-orthogonal planes that includethe coronal direction CO, such planes being optionally different fromthe coronal-mesial plane CM or the coronal-buccal plane CB. Thisautomatically defines a third angular component of the absolute angulardisplacement along a third plane orthogonal to the first and secondplanes.

It is also readily apparent that the total angular displacement, angleθ, between the general coronal direction K and the true coronaldirection CO can be defined with respect to any suitable spatialcoordinate system other than the Cartesian coordinate system XYZ. Forexample, the total angular displacement, angle θ, can be defined withrespect to a spherical coordinate system, referenced to thecoronal-apical z-axis and the mesial-buccal plane MB, and thus via arespective elevation and a respective azimuth corresponding to thegeneral coronal direction K.

By way of non-limiting example, the total angular displacement, angle θ,between the general coronal direction K and the true coronal directionCO is fixed for a particular physical model and corresponding analog tobe used therewith, and can be any specific angle in the range from 0° to90°, or in the range from 0° to about 60°, or in the range from 0° toabout 45°, or in the range from 0° to about 30°, or in the range from 0°to about 20°, or in the range from 0° to about 10°, or in the range from0° to about 5°, or in any other range between 0° and 90°.

Thus, as will become readily apparent, in at least some examples thegeneral coronal insertion direction K of the dental analog with respectto the physical model can be such as to provide an insertion path intothe physical model that is aligned with a longitudinal axis of thedental analog, for example, even in cases where the correspondinglongitudinal axis of the respective dental implant is severely displacedangularly from the true coronal direction CO.

As will become readily apparent, in at least some examples, therespective analog is inserted into the corresponding physical model in adirection opposite to the direction in which the dental implant isinstalled in the corresponding dental structure.

As will also become readily apparent, in at least some examples, therespective analog is inserted into the corresponding physical model in adirection passing through a part of the physical model representative ofdental surfaces 115, from a first location with respect to the physicalmodel corresponding to an inside of the dental structure to a secondlocation with respect to the physical model corresponding to an outsideof the dental structure.

As will also become readily apparent, in at least some examples of theaforesaid method and system, the general coronal insertion direction Kfor an analog with respect to the respective physical model provides aninsertion path into the physical model for the implant that inherentlyavoids collision with at least model dental surface parts of thephysical model that represent the real dental surfaces of the dentalstructure 100. In particular, such collision is avoided with respect tomodel dental surface parts that represent the hard dental surfaces inproximity to the dental implant, for example the teeth adjacent to theimplant. Furthermore the insertion path can be such as to avoid havingto disturb other parts of the physical model, for example the modeldental surface parts thereof that reproduce the soft dental surfaces 120of the dental structure 100 that are in abutting relationship with thedental implant 240, for example the gingival surfaces that surround theimplant.

Referring again to FIG. 1, the spatial disposition P of the implant 240,i.e., the spatial position and orientation in 3D space, with respect tothe dental structure 100, can be defined in many different ways. Forexample, spatial disposition P can be defined via the spatialorientation of longitudinal axis AI of the dental implant 240 withrespect to any chosen coordinate system, together with the spatialposition of a point Q associated with the dental implant 240 (i.e.,having a defined spatial relationship to the dental implant 240) andwhich is at a fixed spatial relationship to the longitudinal axis AI.For example, point Q may be the intersection point between a plane S andlongitudinal axis AI, wherein plane S is coplanar with thecoronal-facing face 248A of prosthesis interface implant part 248. Sucha chosen coordinate system is the same coordinate system as may be usedfor the dental structure 100, or alternatively has a known and fixedspatial relationship with another coordinate system used for the dentalstructure 100.

Referring to FIG. 5, there is illustrated a first example of a physicalmodel 600, configured for enabling a first example of the analog 230 tobe installed therein via an analog insertion opening 607 (in arespective general coronal direction K) to an installed position at aspatial disposition P′ with respect to the physical model 600. As willbe disclosed in greater detail below, and referring to FIGS. 4 and 3,physical model 600 is manufactured according to method 400, for exampleusing system 200.

In FIG. 5, the dental analog 230 is illustrated in the installedposition with respect to physical model 600, at a spatial dispositionP′, the dental analog 230 corresponding to and essentially being, in afunctional sense with respect to the respective prosthesis system 991,for example, a replica of the dental implant 240. Referring also to FIG.6(a), the dental analog 230 comprises, at a coronal end thereof, aprosthesis interface analog part 238 having coronal-facing face 269, anda prosthesis engaging analog part 231 that correspond to and areessentially identical to the prosthesis interface implant part 248,coronal-facing face 248 A and the prosthesis engaging implant part 241,respectively. The dental analog 230 also comprises a longitudinal axisAA corresponding to longitudinal axis AI of the dental implant 240,wherein longitudinal axis AA has the same spatial relationship withrespect to prosthesis interface analog part 238 and to the prosthesisengaging analog part 231 as longitudinal axis AI has with respect to theprosthesis interface implant part 248 and the prosthesis engagingimplant part 241, respectively. Thus, the longitudinal axis AA isaligned with respect to the prosthesis interface analog part 238 and theprosthesis engaging analog part 231 of the analog 230, i.e., alignedwith the centerline of the prosthesis engaging analog part 231, and notnecessarily with a centerline referenced to the external form 270 of thedental analog 230.

Spatial disposition P′ with respect to the installed analog 230 at theinstalled position in the physical model 600 can be defined in anysuitable manner, for example in a similar manner to spatial dispositionP, mutatis mutandis. For example, spatial disposition P′ can be definedvia the spatial orientation of longitudinal axis AA with respect to anychosen spatial coordinate system, together with the spatial position ofa point Q′ associated with the analog 230 and which is at a fixedspatial relationship to the longitudinal axis AA. For example, point Q′can correspond to point Q of the dental implant 240, and can be theintersection point between a plane S′ and longitudinal axis AA, whereinplane S is coplanar with the coronal-facing face 269 of prosthesisinterface analog part 238. Such a chosen coordinate system is the samecoordinate system as may be used for the physical model 600, or has aknown and fixed spatial relationship with another coordinate system usedfor the physical model 600.

The external form 270 of the dental analog 230 is not configured forimplantation in a human, but rather for coupling with the correspondingphysical model 600, at a spatial disposition P′ with respect theretothat replicates the spatial disposition P of the dental implant 240 withrespect to dental structure 100 (see also FIG. 1). In particular, inthis example, and referring again to FIGS. 5 and 6(a), the external form270 of the dental analog 230 comprises a coronal portion 262 adjacent anenlarged apical portion 264. The coronal portion 262 has a maximum widththat is smaller than a maximum width of the enlarged apical portion 264.In this example, the enlarged apical portion 264 having a largercross-sectional area than a cross-sectional area of the coronal portion262. In at least some alternative variations of this example, theenlarged apical portion 264 can instead have a portion thereof thatprojects laterally with respect to the outer surface of the coronalportion 262.

Referring in particular to FIG. 6(a), the coronal portion 262 comprisesa generally cylindrical outer surface 263 about axis AA and that is madeasymmetrical via a flat portion 261. The flat portion 261 extends alongthe longitudinal length of the coronal portion 262 from coronal-facingface 269 to the coronal face 265 of enlarged apical portion 264, thecoronal face 265 being defined on a plane substantially orthogonal toaxis AA. The enlarged apical portion 264 acts as mechanical stoparrangement which abuts shoulder 657 formed in the physical model 600 todefine the limit of penetration of the analog 230 into the physicalmodel 600 in the respective general coronal direction K to the installedposition. The enlarged apical portion 264, in this example, is generallycylindrical and symmetrical about axis AA, but can instead have anyother symmetrical shape about axis AA or any other axis, or can have anasymmetrical shape if desired.

Referring again to FIG. 5, the first example of physical model 600comprises a model dental surface part, also referred to as first modelpart 630, including an outer model surface 661 representing dentalsurfaces of the dental structure 100 that are exposed in the dentalstructure 100, and a second model part 640 including an analoginstallation structure 690. Herein, “analog installation structure” isused interchangeably with “physical analog socket structure”.

Referring to FIG. 1 and FIG. 5, the first model part 630, and inparticular the outer model surface 661, includes parts 610 thatcorrespond to the hard surfaces 110, and parts 620 that correspond tothe soft surfaces 120. The first model part 630 also comprises a coronalopening 650 having a perimeter 655 corresponding to the interface 155between the soft surface 120 and the implant 240 at implant zone 150 ofthe dental structure 100.

Referring to the second model part 640, the analog installationstructure 690 is configured for enabling the analog 230 to be insertedinto the model 600 in a respective general coronal direction K to aninstalled position at spatial disposition P′ with respect to the model600 that replicates the spatial disposition P of the dental implant 240with respect to the dental structure 100. In the installed position, allor part of coronal-facing face 269, prosthesis interface analog part238, and prosthesis engaging analog part 231 of the analog 230 areexposed via the coronal opening 650. This allows a prosthesis system(e.g., comprising dental prosthesis 990, permanent abutment 995 andretainer screw 996, see FIG. 1(a)) to be mounted to the analog 230 withrespect to the physical model 600, in a manner comparable to thatintended for the dental implant 240 in the dental structure 100.

The second model part 640 further comprises a physical model base 609having a base surface 603 and defining an apical portion 606. In thisexample the base 609 has a length and breadth greater than the overalllength and breadth, respectively, of the outer model surface 661, thoughin alternative variations of this example the length and/or the breadthof the model base 609 can be the same as or less than the respectivelength and/or breadth of the outer model surface 661.

In this example the base 609 has a height extending in an apicaldirection away from the outer model surface 661. In this connection thelength and breadth dimensions can be taken along directions orthogonalto the apical-coronal (height) direction. In alternative variations ofthis example, the model base can be relatively thin or nominal, forexample formed by a projection of the outer model surface 661 to aplane, for example orthogonal to the apical direction.

Analog installation structure 690 comprises a passageway 608 extendingin a general coronal direction K from analog insertion opening 607,formed in apical portion 606, to coronal opening 650. The coronalopening 650 is also referred to herein as an access opening to theinstallation structure 690, located at a location in the physical modelcorresponding to the location of the implant site 150. The coronalopening 650 is also referred to herein as an auxiliary opening.

The passageway 608 is elongate, defining a passageway longitudinal axisaligned with said general coronal direction, and in this example of theanalog 230, the passageway longitudinal axis BB is co-axial with alongitudinal axis AA of analog 230 when the analog 230 is in theinstalled position therein. It is to be noted that in other examples ofthe analog 230, the passageway longitudinal axis is not necessarilyco-axial or even parallel with a longitudinal axis AA of the analog whenthe analog is in the installed position therein. It is readily apparentthat analog insertion opening 607 is spaced from the parts of thephysical model corresponding to the implant site 150, in particular thatanalog insertion opening 607 is spaced from coronal opening 650. It isalso readily apparent that analog insertion opening 607 is differentfrom coronal opening 650.

In at least some examples the analog insertion opening 607 is spacedfrom the outer model surface 661. In at least some examples the analoginsertion opening 607 is at a location other than the outer modelsurface 661. In at least some examples the analog insertion opening 607excludes a location in parts of the physical model corresponding to theimplant site 150.

In particular, the passageway 608 is configured, for example via theshape of its internal walls 666, for enabling the analog 230 to beinserted into the physical model 600 in the respective general coronaldirection K to the respective installed position, and defines an analogchamber 665 at the coronal end of passageway 608 for accommodating theanalog 240 at the installed position, at spatial disposition P′ withrespect to the physical model 600. The precise form of the second modelpart 640, and in particular of the analog installation structure 690,thus depends on the particular external configuration of the analog 230,i.e., the external form 270 thereof. Thus, in this example, passageway608 comprises: a first passageway portion 656 having an internal surfacethat is complementary to the outer surface 263 and including acorresponding passageway flat portion (not shown) that is complementaryto analog flat portion 261; a shoulder 657 that is complementary to face265; and a second passageway portion 658 having and internal surfacethat is complementary to the outer surface of enlarged apical portion264 and extends in a general apical direction A to opening 607.

In the installed position, analog 230 forms a tight fit with passageway608, and in particular with analog chamber 665, and this fixes theposition of the analog 230 in the physical model 600 in four degrees offreedom, preventing translation along, or rotation about, two orthogonalaxes that are also orthogonal to the respective general coronaldirection K, and thus also to the longitudinal axis BB, and in thisexample also with respect to the longitudinal axis AA.

The asymmetry of coronal portion 262, in particular the analog flatportion 261, ensures that the analog 230 can be inserted into passageway608, and in particular into analog chamber 665, in only one angulardisposition about the respective general coronal direction K, and thusalso about longitudinal axis BB with respect to the passageway 608. Inthis installed position the analog flat portion 261 is in contact withthe corresponding passageway flat portion, and furthermore such contactfurther prevents rotation between the analog 230 and the physical model600 about the respective general coronal direction K, and thus alsoabout longitudinal axis BB. Furthermore, abutment between the coronalface 265 and the shoulder 657 provides a mechanical stop in the generalcoronal direction K, and thus ensures that the analog 230 can beinserted into passageway 608 to a particular depth along the respectivegeneral coronal direction K, and such contact prevents further coronaltranslation by the analog 230 into the physical model 600 along therespective general coronal direction K, and thus also along longitudinalaxis BB. The analog 230 can be prevented from translating in the generalapical direction out of the installed position in any number of ways,for example by providing a suitable adhesive or a friction fit betweenthe analog 230 and passageway 608, or filling the apical end 602 of thepassageway with a suitable filler or plug, and so on.

In at least this example, the insertion path into passageway 608passageway 608 is defined by (and aligned with) the desired spatialorientation of the axis AA of the analog 230 at the installed positionwith respect to the physical model 600, which in turn matches thespatial orientation of the axis AA of the dental implant 240 withrespect to the dental structure 100. It is also readily evident that thelongitudinal position of the shoulder 657 with respect to the outermodel surface 661 and with respect to longitudinal axis AA is such as toensure that point Q′ of the analog 230 (in the installed position) is ata position with respect to the outer model surface 661 that replicatespoint Q of the dental implant 240 with respect to the dental structure100.

With the dental analog 230 thus fixed in six degrees of freedom withrespect to the physical model 600 in spatial disposition P′ replicatingthe geometrical relationship between the dental implant 240 and thedental structure 100, a prosthesis system (e.g., prosthesis system 991,see FIG. 1(a)) can be designed and/or tested using the dental analog 230while coupled to the physical model 600, and enabling the prosthesissystem to be subsequently mounted to the patient via the dental implant240.

In this example, the implant site 150, in particular the perimeter 655of coronal opening 650 has a shape and dimension complementary to theshape and outer diameter of the coronal-facing face 269. Alternatively,the coronal opening 650 may laterally overlap the periphery of thecoronal-facing face 269 but it is not desired for this overlap to act asa mechanical stop and thus limit or define the relative position betweenthe analog 230 and the passageway 608: for example, and as will bedescribed in greater detail below, the physical model may bemanufactured as a composite model in which part of the physical model inthe vicinity of and overlapping the periphery of the coronal-facing face269 may be made of a soft material, unsuitable or undesirable for actingas a mechanical stop in the general coronal direction for the analog230.

In the example illustrated in FIG. 5 and FIG. 6(a), the respectivegeneral coronal direction K is shown as being oriented close to theorientation of the respective coronal direction CO of the removed tooth.Nevertheless, the example of dental analog 230 illustrated in thesefigures can also be used in situations wherein the dental implant 240 isimplanted in the dental structure 100 at a spatial disposition P havinga relatively large angular displacement with respect to the respectivecoronal direction. FIG. 6(e) illustrates an example of such a situationin which the analog 230 is at a corresponding angular disposition P′,where the respective general coronal direction K and the passageway axisBB are angularly displaced from the respective coronal direction CO ofthe removed tooth by a correspondingly (though not necessarilyidentical) relatively large acute angle, marked in this figure. In casessuch as illustrated in FIG. 6(e), the analog and corresponding implantcan be configured for use with an angulated abutment and prosthesis(marked 990′) to match the orientation of the prosthesis to the adjacentteeth and to provide the correct occlusion with the teeth of theopposite jaw. On the other hand, and as illustrated in FIG. 6(f), analternative design for the analog can be provided with respect to thecase of FIG. 6(e), in which, the spatial disposition P′ of the analog230 represents the spatial disposition of the implant with respect tothe dental structure having a relatively large angular displacement withrespect to the respective coronal direction CO. In the example of FIG.6(f), the respective dental analog is configured to be inserted into thephysical model along a respective general coronal direction K that isparallel or close to parallel with respect to the coronal direction,with the analog having a reference longitudinal axis that is parallel tothe passageway longitudinal axis BB, and parallel with the generalcoronal direction K, but angularly displaced with respect to thecorresponding axis AA of the analog.

It is therefore apparent that for any given configuration of a dentalimplant, implanted at a particular spatial disposition P, a variety ofdifferent analogs can be provided, all such analogs having the sameprosthesis-engaging configuration corresponding to the prosthesisengaging interface of the implant, but having different external forms270 which are, in turn, configured for different configuration of therespective installation structure 690 of the respective physical model600. Thus, in alternative variations of these examples, the analog 230and the analog installation structure 690 of the physical model 600 mayhave different configurations to ensure that dental analog 230 is fixedin six degrees of freedom with respect to the physical model 600 inspatial disposition P′, while enabling insertion of the analog 230 intothe physical model 600 in the general coronal direction K for example.

For example, referring to FIG. 6(b), the enlarged apical portion 265 ofthe example of FIG. 6(a) is omitted from the analog 230, and the analogflat portion 261 does not extend to the apical end of the coronalportion 262, but rather to a location coronally displaced therefrom,thus forming a coronal face 268 displaced from the apical end 267 of thecoronal portion 262. Correspondingly, passageway 608 is formed inphysical model 600 with a shoulder complementary to coronal face 268(and can thus omit shoulder 657), and thus defines the longitudinalposition of the implant 230 in the passageway 608 and thus with respectto the physical model 600 in a manner similar to that provided by thecoronal face 265 and the shoulder 657 of the example illustrated inFIGS. 5 and 6(a), mutatis mutandis.

In another example, referring to FIG. 6(c), the analog flat portion 261of the example of FIG. 6(a) can be omitted from the analog 230, and theenlarged apical portion 264 comprises instead a coronal face having twoportions 265A, 265B both orthogonal to respective general coronaldirection K, and thus also to longitudinal axis AA, but axiallydisplaced from one another via joining walls 265C. Correspondingly,passageway 608 is formed with a stepped shoulder configuration (ratherthan shoulder 657), comprising two shoulders complementary to portions265A, 265B, and which thus defines the longitudinal position of theimplant 230 in the passageway 608 and the angular orientation of theimplant with respect to the physical model 600 about respective generalcoronal direction K, and thus also about longitudinal axis AA.

In another example, referring to FIG. 6(d), the analog flat portion 261of the example of FIG. 6(a) can be omitted from the analog 230, and theenlarged apical portion 264 comprises instead a coronal face 265D thatis not orthogonal to respective general coronal direction K, and thusalso not orthogonal to longitudinal axis AA. Rather coronal face 265D isdefined on a plane inclined to respective general coronal direction K,and thus also to longitudinal axis AA. Correspondingly, passageway 608is formed with an inclined shoulder complementary to inclined coronalface 265D (rather than shoulder 657), which thus defines thelongitudinal position of the implant 230 in the passageway 608 and theangular orientation of the implant with respect to the physical model600 about respective general coronal direction K, and thus also aboutlongitudinal axis AA.

As is also evident from the examples in FIGS. 6(a), 6(c) and 6(d), therelative longitudinal lengths between the coronal portion 262 and theapical portion 264 can be varied as desired, and the passageway 608 iscorresponding formed to receive the implant in the general coronaldirection K.

In another variation of the example of FIG. 6(a) the coronal portion 262can be axisymmetrical about longitudinal axis AA, and instead the apicalportion 264 is asymmetrical (the passageway 608 being complementarilyshaped) to fix the angular disposition between the analog 230 and thephysical model 600 about longitudinal axis AA.

In yet another variation of the example of FIG. 6(a), at least thecoronal portion 262 can be externally threaded, and the passageway 608can be complementarily internally threaded, to fix the angulardisposition between the analog 230 and the physical model 600 aboutlongitudinal axis AA.

In yet another variation of the example of FIG. 6(a), and referring toFIG. 6(g), the passageway 608 has a longitudinal axis BB that isangularly displaced with respect to the corresponding axis AA of theanalog, which has an insertion reference axis parallel to longitudinalaxis BB. Thus, the passageway in the physical model is complementarilyshaped to the analog, and the respective insertion direction K isparallel to axis BB. In this example, while axis AA may be parallel orhave an origination close to that of the coronal direction CO, therespective general coronal direction K can be significantly angularlydisplaced with respect to the coronal direction CO.

In yet another variation of the example of FIG. 6(a), and referring toFIG. 6(h), the passageway 608 has a longitudinal axis BB that isorthogonal or near orthogonal to the true occlusal direction OC, and hasan analog insertion opening 607A on a side of the physical model 600rather than on the base. The passageway in the physical model iscomplementarily shaped to the analog, and the respective insertiondirection K is parallel to axis BB. In this example, the analoginsertion opening 607A can be formed on parts of the physical model 600representing some of the dental surfaces 115, but not any of the dentalsurfaces in the vicinity of and defining opening 650.

A variation of the example of FIG. 6(h) is illustrated in FIG. 6(i),which shows a cross-section of the respective physical model 600 along acoronal-buccal plane, and in which occlusal model surfaces 117′ and sidemodel surfaces 116′ respectively represent occlusal facing dentalsurfaces and adjacent dental side surfaces of the dental surfaces 115 ofthe dental structure 100. In this example, the respective analoginsertion opening 607B is wholly located on a side model surfaces 116′of the physical model 600, representing the gingival surfaces, forexample, of the dental structure 100.

In yet other examples, the insertion path may include a change ofdirection. For example, referring to FIG. 5, another analog insertionopening (not shown) may be provided on the side of the physical model toenable the analog to be laterally inserted into passageway 608, forexample in a buccal or lingual direction (i.e., into or out of thepaper, for example), but at a position still axially displaced alongaxis BB from the implanted position, and then the analog is pushed alongthe axis BB to the implanted position.

In yet another example, and referring to FIG. 7, the enlarged apicalportion 264 of the example of FIG. 6(a) can be omitted from the analog230, and, instead, coronal-facing face 269 abuts a shoulder 657B formedin passageway 608 complementary thereto, the shoulder 657B beingcoplanar with the installed position of the coronal-facing face 269.This arrangement limits the coronal translation of the implant 230 alongpassageway 608 to the installed position with respect to the physicalmodel 600 in a manner similar to that provided by the coronal face 265and the shoulder 657 of the example illustrated in FIGS. 5 and 6(a),mutatis mutandis. In this example, while the analog itself may be ofuniform cross-section, it is evident that the exposed part of thecoronal-facing face 269 has a maximum width dimension that is smallerthan a maximum width dimension of another portion of the analog.

In yet another example, and referring to FIGS. 8 and 8(a), the enlargedapical portion 264 of the example of FIG. 6(a) can be omitted from theanalog 230, and coronal portion 262 comprises visual markings 266 whichare configured to facilitate longitudinal alignment of the analog 230with the installation structure 690. For example, visual markings 266can comprise a mark that can be manually aligned with shoulder 657 orany other suitable datum formed or marked in passageway 608.Alternatively, visual markings 266 can comprise a graduated scaleprovided along the side of the analog 230 that allows the depth ofpenetration of the analog 230 into the physical model 600 to be visuallygauged. In use, the implant 230 can be inserted into passageway 608until this alignment occurs, and the implant 230 is then cemented inplace in its installed position with respect to the physical model 600.

In yet another example, and referring to FIG. 8(b), the analog 230 ofthe example of FIG. 6(a) can include the enlarged apical portion 264,but the analog is axisymmetric enabling free rotation within thepassageway 608 about respective general coronal direction K, and thusalso about axis AA. Apical portion 264 comprises visual markings 266′which are configured to facilitate rotational alignment of the analog230 with respect to the installation structure 690 about respectivegeneral coronal direction K, and thus also about axis AA. For example,visual markings 266′ can comprise a mark that can be manually alignedwith a corresponding mark or other datum provided in the passageway 608,while the shoulder 657 acts as a mechanical stop. In use, the implant230 can be inserted into passageway 608 until the enlarged apical end264 is in abutment with shoulder 657, and then rotated therein aboutaxis AA until this rotational alignment occurs, and the implant 230 canthen be cemented in place in its installed position with respect to thephysical model 600. Alternatively, the enlarged apical portion 264 ofthe example of FIG. 6(a) can be omitted from the analog 230, the visualmarkings 266′ being provided, instead, on an apical end of the coronalportion 262, and in addition, visual markings 266 are also provided, ina similar manner to that of the example of FIGS. 8 and 8(a), mutatismutandis, to also facilitate longitudinal alignment of the analog 230with the installation structure 690. In use, the implant 230 can beinserted into passageway 608 and rotated therein until this longitudinaland rotational alignment occurs, and the implant 230 is then cemented inplace in its installed position with respect to the physical model 600.

It is to be noted that in the above examples and in other examples ofthe analog 230 and of the corresponding physical model 600, theasymmetry of the coronal portion 262 may be achieved in a differentmanner to that illustrated with respect thereto to define the angulardisposition P′ of the analog 230 with respect to the passageway 608, andthus with respect to the physical model 600. For example, additionalflat portions, similar to flat portion 261 but angularly displacedtherefrom about longitudinal axis AA may be provided on the coronalportion 262. Alternatively, one or both of the coronal portion 262 andapical portion 264 can be formed having a non-axisymmetriccross-section, for example as a respective prismatic member having apolygonal cross-section (corresponding to a regular or irregularpolygon), or having an oval cross-section, for example. In each case thepassageway 608 is complementarily shaped to allow insertion of theanalog in the general coronal direction to its installed position.Additionally or alternatively, a keyway may be formed in each one of theanalog 230 and the passageway 608 of the physical model 600, and acorresponding key inserted when both keyways are aligned to fix therelative disposition between the analog 230 and physical model 600 in atleast five degrees of freedom.

It is also to be noted that in the above examples and in other examplesof the analog 230 and of the corresponding physical model 600, one orboth of the coronal portion 262 and apical portion 264 are each formedhaving a generally uniform cross-sectional form along the longitudinalaxis AA. Alternatively, and as illustrated in FIG. 9, in at least onevariation of these examples or in at least another example, the coronalportion 262 may have a cross-section 262A that tapers in the generalcoronal direction, and the passageway 608 is complementarily tapered, tothereby define the longitudinal position of the implant 230 in thepassageway 608 and thus with respect to the physical model 600; it isreadily evident that additionally or alternatively, the apical portion264 can be omitted, or the apical portion 264 can be formed withcoronally tapering cross-section.

It is also to be noted that in at least some of the above examples andin other examples of the analog 230 and of the corresponding physicalmodel 600, at least the exposed part of the respective coronal-facingface 269 (when the analog is in the respective installed position in thephysical model 600) has a maximum width dimension that is smaller than amaximum width dimension of another portion of the analog. This ensuresthat these examples of the analog can be inserted into the physicalmodel 600 in a direction that does not penetrate into the externalsurface 661, for example along a particular general coronal direction K,and at the same time limits penetration of the analog into the model toensure that it is at the installed position at the end of penetration.The other portion of the analog having a greater maximum width than atleast the exposed part of the respective coronal-facing face 269 can beat any desired location along the analog, for example at the opposed endthereof with respect to the coronal-facing face 269, or inbetween. It isreadily evident that the maximum width differential can be achieved byproviding this part with a larger cross-sectional shape or with aprotrusion, as compared with the at least the exposed part of therespective coronal-facing face 269.

Referring to FIG. 3, an example of a system 200 for manufacturing aphysical model, such as for example physical model 600, comprises afirst subsystem 260 for generating a virtual (three-dimensional) modelof the patient's dental structure 100 that includes the dental implant240, operatively connected to a second subsystem 280 for manufacturingphysical model 600 based on and corresponding to the virtual model, thephysical model 600 being configured for enabling a physical analog 230(corresponding to the dental implant 240) to be coupled, as alreadydescribed in greater detail above.

The first subsystem 260 comprises a microprocessor or any other suitablecomputer system suitably programmed for operating on a virtual model ofthe aforesaid dental structure 100 to provide suitable manufacturingdata to second subsystem 28, as will be disclosed in greater detailbelow with respect to the method 400. In this example, the computersystem 260 comprises an input interface 210 such as a keyboard, mouse,tablet, and so on, an output device such as display 220, a processingunit 230, and a memory 235. Herein “display” refers to any device orsystem for delivering a presentation, which can include one or more ofany information, data, images, sounds, etc, and thus the delivery can bein visual and/or audio form.

In this example, the subsystem 260 also comprises a scanner 250 that isconfigured for providing 3D surface data of surfaces, in particular ofthe dental structure 100 (or alternatively of an already existingphysical model of the dental structure 100), including the hard dentalsurfaces 110 and soft dental surfaces 120 thereof, and also includingthe dental implant site 150. The scanner 250 is also configured forproviding data relating to the spatial disposition P of the implant 240with respect to the dental structure 100.

The scanner 250 is operatively connected to the computer system 260 andinteracts therewith, and the subsystem 260 and/or the scanner 250 aresuitably programmed for reconstructing such surfaces from the surfacedata provided, to provide a virtual model 500 of the dental structure100. Suitable examples of such scanners are well known, and can include,for example, an intra-oral scanner marketed under the name of iTero (byCadent Ltd., USA) which uses a hand held probe for determining threedimensional surface data based on confocal focusing of an array of lightbeams, and may optionally provide color data of the intraoral cavity inaddition to the 3D surface data.

A scanning abutment 246 can be provided, which in use can be mounted tothe dental implant 240 via the prosthesis interface part 248 and theprosthesis engaging part 241, and subsequently scanned directly orindirectly by the scanner 250. The scanning abutment 246 ischaracterized in having suitable 3D attributes, for example the scanningabutment 246 is shaped, and/or comprises suitable markers or otherpositional indicators on the visually exposed part thereof when mountedto the implanted implant 240, that provide information to enable thespatial disposition P of the dental implant 240 with respect to thedental structure 100 to be determined. In some cases, an impressionabutment or a healing abutment can be used as a scanning abutment.

In alternative variations of this example of system 200, the scanner 250can be omitted and the virtual model 500 can be provided to thesubsystem 260 in any other suitable manner, for example via externalvirtual model source 290, which includes virtual model 500 having beengenerated in any suitable manner, including inter alia using suitableother scanning techniques, for example based on optical methods, directcontact methods, X-ray scanning, CT scanning, MRI scanning,ultrasound-based scanning, or any other type of scanning can be used,applied directly to the patient's dentition or to an impression or othernegative model of the patient's dentition, or to an existing physicalmodel thereof, as appropriate.

In any case, the subsystem 260 manipulates and operates on the virtualmodel 500 of the aforesaid dental structure 100 as disclosed below inthe context of method 400 to generate manufacturing data formanufacturing the respective physical model 600, and this manufacturingdata is provided to second subsystem 280.

The second subsystem 280 comprises a computer controlled manufacturingsystem configured for manufacturing the physical model 600 from themanufacturing data, which for example may be referenced to a machinecoordinate system C. While in this example, the manufacturing processitself is a material removing process, such as CNC milling for example,in alternative variations of this example part or all of themanufacturing process can include a material additive process, forexample a rapid prototyping process, for example using a 3D systemstereo lithography machine, or can include any other suitablecomputer-controlled manufacturing process.

Referring to FIG. 4, an example of a method 400 for manufacturing aphysical model, such as for example physical model 600, and which can becarried out using system 200, for example, broadly includes thefollowing steps 420 and 450:

-   -   Step 420—receiving a virtual model of the physical dental        structure and a virtual analog installation structure (also        referred to herein interchangeably as a virtual analog socket        structure) in association with said virtual model, said virtual        analog installation structure being based on the dental analog;    -   Step 450 using said virtual model, manufacturing a physical        model corresponding to said virtual model, the physical model        being provided with an analog installation structure based on        said virtual analog installation structure and thereby        configured for enabling the dental analog to be inserted into        said physical model through an analog insertion opening, wherein        said analog insertion opening is spaced from a location in the        physical model corresponding to the implant site in the physical        dental structure.

In at least one variation of this example, and referring to FIG. 4(b),steps 420 and 450 can be as follows:

-   -   Step 420—providing a virtual model of the physical dental        structure including a virtual implant spatial disposition with        respect to said virtual model corresponding to a physical        implant spatial disposition of the dental implant with respect        to the physical dental structure;    -   Step 450—using said virtual model, manufacturing a physical        model corresponding to said virtual model, the physical model        being provided with an analog installation structure configured        for enabling a physical analog, corresponding to the dental        implant, to be inserted in a general coronal direction with        respect to said physical model to an installed position therein        having an analog spatial disposition with respect to said        physical model corresponding to said physical implant spatial        disposition, wherein said analog installation structure is        previously defined in said virtual model.

In any case, the method 400 assumes that implant 240 has already beenimplanted in the dental structure 100 of the patient, and it is to benoted that implantation of implants in the intra oral cavity of patientsis well known in the art. The method 400 also assumes that a particulartype of analog 230 according to the first aspect of the presentlydisclosed subject matter, and corresponding to the dental implant 240,has been chosen, having a known or determinable external form 270.

Referring to each step in turn, step 420 comprises initially receiving,for example acquiring, an accurate three dimensional virtual model 500of the dental structure 100, which as already stated includes theimplant 240 and thus forms the focus of the particular implant procedurefor a particular patient. Herein the term “virtual model” is synonymouswith, and can be referred to interchangeably as, “three-dimensionalmodel”, “3D model”, “virtual model”, “3D representation”, “3D digitizeddata”, and the like. Referring also to FIG. 3, the virtual model 500 canbe provided by scanning the intra-oral cavity dental structure directlyin-vivo using the scanner 250 of system 200. Alternatively the virtualmodel 500 can be provided in any other any other suitable manner, forexample via external virtual model source 290, i.e., including interalia using suitable other scanning techniques, for example based onoptical methods, direct contact methods, X-ray scanning, CT scanning,MRI scanning, ultrasound-based scanning, or any other type of scanningcan be used, applied directly to the patient's dentition or indirectlythereto, for example applied instead to an existing physical modelthereof, as appropriate.

The virtual model 500 includes, in addition to a virtual representationof dental surfaces 150 of the dental structure 100 (i.e., 3D informationof the soft dental surfaces 120 and hard dental surfaces 110 at least inthe vicinity of the implant zone 150), sufficient spatial (3D) dataregarding the implanted implant 240 so that its spatial disposition Pwith respect to the dental structure 100, can be also be modeled withrespect to the virtual model 500. The spatial disposition P of theimplant 240 can be determined using at least two different scanningmethods, to provide virtual implant spatial disposition data.

In a first scanning method, a first scanning procedure is applieddirectly to the dental structure 100 (the dental implant 240 beingexposed to the intra-oral cavity) to enable creation of the virtualmodel 500 of the dental structure 100, to thereby provide an accuratevirtual representation of dental surfaces 150 of the dental structure100. Then, scanning abutment 246 is mounted to the dental implant 240and a second scanning procedure is applied to the dental structure 100with the scanning abutment 246 in situ, generating an auxiliary virtualmodel which includes a virtual portion thereof corresponding to thescanning abutment 246. Since the scanning abutment 246 has known 3Dattributes, and the geometric relationship between the scanning abutmentand the dental implant 240 is also fixed and known, analysis of thisportion of the auxiliary virtual model provides information about thespatial disposition P of the dental implant 240 with respect to thedental structure 100, and thus enables this spatial disposition P to bemodeled with respect to the first auxiliary virtual model to providecorresponding virtual spatial disposition data VP. Of course, the secondscanning procedure can instead precede the first scanning procedure, inwhich case the scanning abutment 246 is removed from the dental implant240 prior to proceeding with the first scanning procedure. In any case,a registration step can then be performed between the auxiliary virtualmodel and the virtual model 500, for example by matching correspondingvirtual dental surfaces thereof, in particular by matching correspondingexternal hard virtual dental surfaces thereof, to provide the relativevirtual disposition data VP of the implant with respect to the virtualmodel 500 from the virtual disposition already determined for theauxiliary virtual model. Thus, the first scanning procedure provides thevirtual representation of dental surfaces 150 of the dental structure100 with unobscured surface details of the soft tissues in the vicinityof and around the periphery of the prosthesis engaging part 248, i.e.,at interface 155, while the second scanning procedure provides thenecessary information to determine the spatial disposition P of theimplanted implant 240 with respect to the dental structure 100. Thistwo-step scanning procedure can be of particular benefit when thedetails of the implant 240 are at least partially obscured by the softtissues in the vicinity of the prosthesis engaging part 248, and/or,where the scanning abutment 246 mechanically interferes with (forexample presses against and deforms) the soft tissues in the vicinity ofthe prosthesis engaging part 248.

In a second scanning method, only a single scanning procedure is applieddirectly to the dental structure 100 (i.e., without any scanningabutment 246 being mounted thereto). In this scanning procedure at leasta portion of the prosthesis engaging part 248 is exposed and capturedduring the scanning procedure, this portion being uniquely identifiablewith respect to the dental implant 240. Analysis of a virtual portion ofthe virtual model 500 corresponding to the exposed prosthesis engagingpart 248 enables this virtual portion to be matched to the geometry ofthe dental implant 240, which thus provides information about thespatial disposition P of the dental implant 240 with respect to thedental structure 100. In turn, this enables this spatial disposition Pto be modeled with respect to the virtual model 500 to provide acorresponding virtual spatial disposition data VP of the virtualequivalent of the dental implant 240 with respect to the virtual model500.

The virtual spatial disposition data VP thus includes dental implantdata representing the location and orientation of the dental implant 240with respect to the dental surfaces 115.

Alternatively, an indirect scanning technique can be used if a firstprior physical model of the dental structure 100 (i.e., with the dentalimplant 240 already implanted in the dental structure 100) alreadyexists, the aforementioned first scanning procedure of the firstscanning method, or the second scanning method, may be applied to thisfirst prior physical model rather than to the dental structure 100 i.e.,instead of scanning the actual intraoral cavity of the patient.Furthermore, if there also exists a second prior physical model of thedental structure 100, obtained when the scanning abutment 246 wasmounted thereto, the aforementioned first scanning procedure of thefirst scanning method may be applied to this second prior physical modelrather than to the intraoral cavity of the patient. The first priorphysical model can be provided, for example, in a conventional mannervia a first physical impression of the dental structure 100, includingthe exposed implant 240 and subsequently casting the first physicalimpression with paste. The second prior physical model can be providedin a similar manner, for example via a second physical impression of thedental structure 100 taken with the scanning abutment 246 mounted to theimplant 240 and subsequently casting the second impression with paste.

Thus, with respect to the virtual model 500, virtual spatial dispositiondata VP is determined, representative of the physical spatialdisposition P of the dental implant 240 with respect to the dentalstructure 100.

For example, virtual spatial disposition data VP can be defined withrespect to virtual model 500 in a similar manner to spatial dispositionP or spatial disposition P′, mutatis mutandis, i.e., can include thevirtual spatial orientation of a virtual longitudinal axis VA, and thespatial position of a point VQ associated with a virtual analog 730(corresponding to the physical analog 230), point VQ being at a fixedspatial relationship with respect to the axis VA.

Referring to FIG. 10, virtual model 500 comprises a first externalsurface 561 virtually representative of dental surfaces 115 of saiddental structure 100, including first virtual portions 509 correspondingto the hard dental surfaces 110, second virtual portions 508corresponding to the soft dental surfaces 120, and a third virtualportion 502 corresponding to the interface 155 between exposed part ofprosthesis engaging part 248 and soft dental surfaces 120.

Additionally, the virtual model 500 is operated on and modified todefine a fully enclosed virtual volume corresponding to the enclosedvolume of the respective physical model 600 that is to be manufactured.For example, and also referring again to FIG. 5, the virtual model 500can be modified to include a virtual model base 506 corresponding to thedesired physical model base 609, and comprising a respective externalbase surface 507 corresponding to the desired physical base surface 603.The virtual model base 506 can be generated in any number of ways. Forexample, a rectangular parallelepiped, or other prismatic shape or anyother suitable shape, can be defined having a length and breadthgreater, for example about 10% greater, than the overall length andbreadth, respectively, of the first external surface 561, and a heightfor example about the same as the overall height of the first externalsurface 561. The base surface 507 thus generated is displaced in anapical direction A away from the first external surface 561, and thefirst external surface 561 is smoothly joined to the external basesurface 507 in a virtual manner to create the enclosed virtual volume.The external base surface 507 is thus different from first externalsurface 561 and does not correspond to physiological surfaces, includingdental surfaces, of said dental structure 100.

At least a part of the external base surface 507 is displaced from theaforesaid first external surface 561 in an apical direction A withrespect thereto and away from the third virtual portion 502, and definesa virtual apical portion 501 corresponding to the desired physicalapical portion 606 of the physical model 600.

Referring to FIG. 4(a), step 450 comprises a number of sub-steps, asfollows:

-   -   Step 470—defining in said virtual model 500 a virtual analog        socket structure (i.e., the virtual analog installation        structure 590), for virtually accommodating therein a virtual        analog (corresponding to the physical analog) in a virtual        installed position (corresponding to the desired installed        position of the physical analog in the physical model). In other        words, the virtual analog installation structure 590 corresponds        to the desired physical installation structure 690.    -   Step 480—generating machine instructions for manufacturing the        physical model 600 based on said virtual model 500 and the        virtual analog installation structure 590.    -   Step 490—using the machine instructions, manufacturing the        physical model 600.

Herein, “virtual analog” is used interchangeably with “virtual analogstructure”.

Referring to step 470, this can include three sub-steps: step 470A, step470B, and step 470C. In step 470A, and referring again to FIG. 10, thegeometry of the appropriate virtual analog installation structure 590corresponding to the desired physical installation structure 690, isprovided, having corresponding 3D characteristics such as to ensure thatvirtual analog 730 can be virtually installed in the virtual analoginstallation structure 590 to a virtual installed position with respectthereto corresponding to the installed position of the dental analog 230with respect to the corresponding physical installation structure 690,i.e. at virtual spatial disposition data VP, to define their relativepositions in six degrees of freedom. The virtual analog installationstructure 590 includes virtual passageway 708 having virtual internalwalls 766 configured for allowing virtual insertion of the respectivevirtual implant 730 along the respective insertion direction to avirtual installed position, corresponding to the desired physicalpassageway 608 and internal walls 666, mutatis mutandis. Thus, andreferring to the example of dental analog 230 and physical model 600illustrated in FIG. 5 and FIG. 6(a), the virtual internal walls 766define a virtual analog chamber 765, and passageway 708 comprises afirst passageway portion 756, a shoulder 757, and a second passagewayportion 758, corresponding to and having virtual 3D characteristicscorresponding to the physical 3D characteristics required for the firstpassageway portion 656, shoulder 657, and second passageway portion 658.It is to be noted that at this point the second passageway portion 758can have a different axial length than that of the eventual secondpassageway portion 658. These virtual components of passageway 708 arethus determined from the virtual external form 770 of the respectiveanalog 730 is a manner similar to that described above for thepassageway 608 of physical model 600 of FIG. 5 in the context of theexternal form 270 of the analog 230, mutatis mutandis.

Thus, the virtual analog installation structure 590 can be modeled forany type of implant 230, mutatis mutandis, having any external form 270,for example as illustrated in the figures, comprising a virtualpassageway 708 having virtual internal walls 766 configured for allowingcoronal insertion of the respective virtual implant 730 to a virtualinstalled position based on the external form 270 of the respectiveanalog 230.

Thus, for example, it is possible for the first subsystem 260 to includein memory 235 (or in another memory operatively connected to the firstsubsystem 260) a library of virtual analog installation structures 590,each corresponding to one of a plurality of different types of dentalanalogs 230, in particular of the respective external forms 270 thereof,and the appropriate virtual analog installation structure 590 can beretrieved and operated on in steps 470B and step 470C below byidentifying the corresponding virtual analog 770, which in turncorresponds to the actual dental analog 230 that has been chosencorresponding to the dental implant 240.

Alternatively, the appropriate virtual analog installation structure 590can be imported to the first subsystem 260 from another external source.

In step 470B, the virtual analog installation structure 590 provided instep 470A is virtually aligned with respect to the virtual model 500 atvirtual spatial disposition data VP to ensure that a virtual analog 730can be virtually inserted to a virtual installed position thereincorresponding to the installed position of the dental analog 230 in thephysical model 600, the spatial disposition P′, and which in turncorresponds to the spatial disposition P. This virtual alignment isrelatively straightforward since the virtual spatial disposition of thevirtual analog 730 with respect to the virtual analog installationstructure 590 is fixed in six degrees of freedom at the virtualinstalled position, and since in the virtual installed position thevirtual analog 730 will be at the already determined virtual dispositionVP with respect to the first model 500. For example, the virtual analog730 can be registered with respect to the virtual model 500 by aligningthe virtual analog 730 at virtual spatial disposition data VP, and thenregistering the virtual analog installation structure 590 with thevirtual analog 730, after which the virtual analog 730 can be removed.

In any case, the result is that the aligned virtual analog installationstructure 590 is referenced to the same spatial/coordinate system as thevirtual model 500.

Optionally, the aligned virtual analog installation structure 590 can befurther modified, as necessary to ensure compatibility with the virtualmodel base 506, in particular to define virtual analog insertion opening707 formed in virtual apical portion 706, corresponding to analoginsertion opening 607 formed in apical portion 606. Thus, if necessary,the virtual passageway 758 can be extended in a general apical directionaligned with the virtual longitudinal axis VA, or shortened, to ensuresuch compatibility, and the virtual analog insertion opening 707 can bevirtually defined as the intersection of virtual passageway 758 withvirtual apical portion 706.

It is readily apparent that virtual analog insertion opening 707 isspaced from the parts of the virtual model corresponding to the implantsite 150, in particular that virtual analog insertion opening 707 isspaced from virtual coronal opening 503. It is also readily apparentthat virtual analog insertion opening 707 is different from virtualcoronal opening 503.

In at least some examples the virtual analog insertion opening 707 isspaced from the outer model surface 661. In at least some examples theanalog insertion opening 607 is at a location other than the firstexternal surface 561. In at least some examples the virtual analoginsertion opening 707 excludes a location in parts of the virtual modelcorresponding to the implant site 150.

Finally, a part of the virtual model 500 circumscribed by third virtualportion 502 is removed to provide virtual coronal opening 503, and thecoronal end of the virtual analog installation structure 590 isvirtually joined to the third virtual portion 502. The virtual analoginstallation structure 590 is thus open in a virtual sense at itscoronal end via coronal opening 503, and at its apical end via virtualanalog insertion opening 707.

In step 470C the virtual analog installation structure 590 can bevirtually combined with the virtual model 500 to generate a modifiedvirtual model 500′.

Referring to FIG. 4(c), it is thus readily apparent that the virtualmodel 500 can be created using a computer system, and implementing thefollowing broad steps:

-   -   Step 472—receiving a virtual representation of dental surfaces        of the physical dental structure with dental implant data        representing a location and orientation of the dental implant        with respect to the dental surfaces;    -   Step 474—receiving a virtual analog structure, the virtual        analog structure being based on said dental implant; and    -   Step 476—creating the virtual model based on:        -   said virtual representation of dental surfaces; and        -   a virtual analog socket structure based on said virtual            analog structure and said dental implant data, and having an            virtual analog insertion opening that is spaced from parts            of the virtual model corresponding to dental surfaces and            the implant site.

It is also readily apparent that the virtual analog socket structure,i.e., the virtual analog installation structure 590, is configured forvirtually receiving therein the analog virtual model 730 via the virtualanalog insertion opening 707 and along an insertion path, wherein theinsertion path is along an insertion direction including at least oneof:

-   -   a general coronal direction K;    -   a non-apical direction;    -   a direction passing through the virtual representation of dental        surfaces, i.e., first external surface 561, from a first        location F1 with respect to the virtual model 500 corresponding        to an inside D1 of the dental structure 100 to a second location        F2 with respect to the virtual model 500 corresponding to an        outside D2 of the dental structure (see FIG. 5 and FIG. 10).

Referring again to FIG. 4(a), in step 480 the modified virtual model500′ is suitably operated on to provide suitable machine instructions Mto enable in step 490 computer controlled manufacture of the physicalmodel 600 including the physical installation structure 690corresponding to the virtual analog installation structure 590, forexample using subsystem 280 (FIG. 3).

Alternatively, and referring again to FIG. 3, manufacturing step 490 hastwo stages. In this case, step 470C can optionally be omitted, and instep 480 the virtual model 500 is suitably operated on to provide afirst set of machine instructions M1 for computer controlled manufactureof part of the physical model 600 excluding the physical installationstructure 690. The virtual analog installation structure 590 is alsosuitably operated on to provide a second set of machine instructions M2to finish the physical model 600 by the computer controlled manufactureof the physical installation structure 690 therein.

The exact nature of the machine instructions will depend, inter alia, onthe type of computer controlled manufacture being used in step 490, forexample CNC machining or rapid prototyping, and can be carried out usingthe second subsystem 280, for example.

A feature of CNC controlled manufacturing process of the model 600according to this and at least some other examples of the presentlydisclosed subject matter is that the machine instructions for producingboth, the external surface 661, base 609, chamber 665, passageway 608and opening 607 of the model 600, are derived from the same virtualmodel 500 and are thus referenced to the same machine coordinate systemC. This enables the same CNC controlled manufacturing system to be usedfor machining the external surface 661 and base 609 of the physicalmodel 600, either in parallel or in series, with chamber 665, passageway608 and opening 607 of the model 600, in an accurate and consistentmanner, and in one machining operation or procedure. Further, there isno need for an intervening scanning operation or procedure to determinethe 3D shape of the outer surface 661 or base 609, and then attempt toalign the CNC machining of the cavity thereto, as can be required if theouter surface 661 on the one hand, and chamber 665, passageway 608 andopening 607 of the model 600, on the other hand, are manufactured usingdifferent methods or which are not based on the same virtual model. Themanufacturing process according to at least this example can thus alsobe relatively quick and efficient.

The aforesaid computer controlled machining process can thus provide ahigh degree of dimensional accuracy at least in terms of the positionand alignment of the chamber 665, passageway 608 and opening 607 of themodel 600, with respect to the outer surfaces 661, and thus in terms ofthe position and alignment of analog 230 with respect to the model 600when affixed therein, as the machining process for both the cavity 665and chamber 665 on the one hand, and the passageway 608 and opening 607of the model 600 on the other hand, are based on the same coordinatesystem.

In alternative variations of this example, the model 600, including theexternal surface 661, base 609, chamber 665, passageway 608 and opening607 can be concurrently manufactured using any suitable manufacturingmethods, for example rapid prototyping manufacturing methods.

In yet other alternative variations of this example, the model 600,including the external surface 661 and base 609 can be manufacturedusing a first manufacturing method, for example rapid prototypingmanufacturing methods, while chamber 665, passageway 608 and opening 607can be subsequently manufactured on this model using a secondmanufacturing method, for example CNC material removal manufacturingmethods. Alternatively, model 600, can be produced using any othersuitable computer-controlled manufacturing technique based on thevirtual model 500.

The physical model 600, produced by CNC material removal methods and/orrapid prototyping methods, can be formed entirely of a hard material (orat least external surface 661 is formed entirely of a hard material),for example from a suitable hard machinable plastic or polymericmaterial or from hard materials commonly used in rapid prototypingmanufacturing processes.

The physical model 600 can thus be made having uniform hardness.Alternatively the physical model can be formed as a composite physicalmodel, for example as disclosed below regarding the second aspect of thepresently disclosed subject matter for composite physical model 800,mutatis mutandis.

Once the physical model 600 with its respective installation structure690 is completed, the analog 230 can be inserted into the physical model600 in a general coronal direction K to the respective installedposition, via apical base opening 607.

It is to be noted that the physical model 600 can optionally be formedwith alignment features that allow the physical model 600 to be alignedwith a physical model of the opposite jaw to provide proper occlusion,and the alignment features are first defined in a virtual manner in thevirtual model 500, for example as disclosed in U.S. Pat. No. 7,220,124,US 2007/0077537 and US 2007/0154867, co-assigned to the presentAssignee. Such a physical model 600 with alignment features can beprovided according to the following method, for example:

-   -   (a) using a computer system:        -   providing a three dimensional (3D) virtual dentition model            of a patient's dentition including virtual model components            corresponding to at least a part of each jaw thereof, and            including the dental structure 100;        -   providing 3D data representative of at least the spatial            relationship between said jaws in occlusion;        -   incorporating in said 3D virtual dentition model, one or            more digitally created structural reference components            defining an alignment arrangement for said 3D virtual            dentition model based on said 3D data so as to define an            updated 3D virtual dentition model, said one or more            structural reference components configured to provide            virtual occlusion alignment between said model components            according to the spatial relationship; and    -   (b) following step (a), preparing a physical three dimensional        (3D) model including said physical model 600 and physical model        components that respectively represent said virtual model        components, based on said updated 3D virtual dentition model        obtained in step (a), wherein said physical model components are        produced incorporating one or more physical structural reference        components respectively corresponding to one or more digitally        created structural reference components to enable selectively        providing physical occlusion alignment between said physical        model components corresponding to said virtual occlusion        alignment.

Alternatively, the physical model 600 can be configured for mountingonto any dental articulator.

According to the first aspect of the presently disclosed subject matter,a family of analogs may be conceived and provided, wherein each analog230 of the family has the same external form 270, but wherein theanalogs 230 in the family differ from one another in having a respectiveprosthesis interface analog part 238 and corresponding prosthesisengaging analog part 231 that is implant-specific, i.e., that correspondto the prosthesis interface implant part 248 and the prosthesis engagingimplant part 241 of a specific type of dental implant, for compatibilitywith a particular type or make of prosthesis/permanent abutmentconfiguration. For example, each of the analogs 230 in the family maycorrespond to a different one of a plurality of commercially availabledental implants 240. This allows the method 400 to be effectivelyapplied to a wide range of cases where the dental implant 240 can bechosen for compatibility with any one of a range of suchprosthesis/permanent abutment configuration, while the external form 270of the analog 230 is effectively standardized, enabling the form of theopening 607, passageway 608 and chamber 665 formed in the physical model600 can be standardized, and likewise the virtual equivalents of thesecomponents can also be standardized.

In another example according to the first aspect of the presentlydisclosed subject matter, a particular desired analog is not originallysuitable for, or is unable to be, press-fitted into acomplementarily-shaped chamber, formed in the physical model, in ageneral coronal direction. For example, and referring to FIG. 11, thedesired analog 230′ can be a commercially available analog that cancomprise laterally projecting protrusions designed for anchoring theanalog in a plaster model when the model is cast using prior artmethods, in which the analog is first aligned in the mold prior tocasting. The system and method according to the first aspect of thepresently disclosed subject matter can be applied in at least twodifferent ways, for example as follows.

In a first such application of system and method according to the firstaspect of the presently disclosed subject matter, and referring to FIG.11, the physical analog 230′ is embedded in a jacket 300 to form acomposite analog 310. For example, the jacket 300 is made from amachinable material, which is milled or otherwise machined in situ onthe analog 230′ to have a relative smooth external shape 315 that isreadily insertable in the general coronal direction K, into the in thephysical model, referred to herein by the reference numeral 601, andwhich enables the composite analog 310 to be fixed therein in sixdegrees of freedom at spatial disposition P′. Thus, the external shape315 can correspond to or be similar to the external form 270 asdescribed above to any one of the examples of analog 230, for example.On the other hand, the physical model 601 has a respective analogphysical installation structure 690, for example including passageway321 and chamber 320, and model base opening 322.

The shape and relative position of the outer surface 315 of the jacket300 that is to mate against the internal surface 325 of chamber 320 canbe predefined, for example. The shape and relative position of the outersurface 315 of the jacket 300 that is to mate against the internalsurface 325 of chamber 320 can be predefined. The jacket 300 is formedon the analog 230′—for example the analog 230′ is cast or otherwiseembedded in a blank of material, and the jacket 300 is machined until adesired form is provided for outer surface 315. Alternatively, a castmaterial can be poured into a precision mold of a predefined internalshape, while analog 230′ is being held in a predefined spatialrelationship with respect thereto by an accessory such as a suitable jigor the like.

The method steps as disclosed above and with reference to FIG. 4 areapplicable to this example of physical model 601, mutatis mutandis, withthe main difference that in general at least some of the steps thereinrelating to the analog 230, chamber 665, passageway 608 and opening 607,and their virtual equivalents, can be applied, in this example, to thecomposite analog 310, respective chamber 320, respective passageway 321and respective opening 322 instead, mutatis mutandis, while step 420 forthe second example is substantially the same as for the first examplerelating to physical model 600 mutatis mutandis.

In step 470, though, the virtual analog 730, while now representative ofthe physical analog 230′ rather than analog 230, is furtherrepresentative of the jacket 300, and thus in particular corresponds tothe composite analog 310. In any case, in step 470, the resultingcomposite analog 310 can be scanned, for example, to generate thecorresponding virtual analog 730.

In step 450, the outer surface and the chamber 320 of the physical model601 are manufactured in a similar manner to that for physical model 600,mutatis mutandis, and the composite analog 310 can then be installedinto the chamber 320 via opening 322 and passageway 321 in a generalcoronal direction K such that the analog 230′ is aligned with the model601 in spatial disposition P′. The physical model 601 can be made havinguniform hardness, for example as disclosed herein for physical model600, mutatis mutandis, or can be formed as a composite physical model,for example as disclosed below for composite physical model 800, mutatismutandis. In any case, once the physical model has been manufactured,the composite analog 310 is inserted into chamber 320 via opening 322and passageway 321.

Alternatively, and in a second such application of system and methodaccording to the first aspect of the presently disclosed subject matter,a physical model of the dental structure 100 is provided in a similarmanner to that disclosed herein for the above examples, mutatismutandis, with some differences. Referring to FIG. 12, the firstdifference is that the respective chamber 665″ and respective passageway608″ are provided being significantly larger (i.e., having largercross-section) than required for accommodating the analog 230′ in atight fit configuration, and the respective chamber 665″ and respectivepassageway 608″ can be of any desired shape so long as the analog 230′can be inserted therein in a general coronal direction, with a lateralclearance 662 therebetween, to the installed position at spatialdisposition P′. In this case, the virtual analog installation structureis generated to provide a corresponding clearance for the virtual analogcorresponding to the analog 230′. Once the physical model 603 ismanufactured, an accessory in the form of an accessory in the form jig700 is used for holding the analog 230′ within the chamber 665″, viaopening 607″ and passageway 608″ in the desired position and orientationtherein, i.e., in spatial disposition P′ having been inserted therein ina general coronal direction K. A filling and fixing material, forexample epoxy resin, is then introduced in the clearance gap 662 andallowed to set, cementing the analog 230′ in place, after which the jig700 can be disengaged from the analog 230′ and from the model 603.

The jig 700, according to a first example thereof, comprises a base 710,and a substantially rigid, inverted U-shaped strut 720, having one arm722 rigidly attached to the base 710 and a second arm 724 having a freeend 725 onto which an analog 230′ can be mounted at apical end thereof239″ (opposed to the abutment receiving end thereof) in a known andunique spatial relationship with respect thereto. There is thus a uniqueand fixed spatial relationship between the end 725 and the base 710. Theshape of the jig is only illustrative, and any suitable arrangement canbe used that has a fixed geometrical relationship between themodel-engaging base and the analog apical end. Furthermore, the matingplatform 670 is attached to the model base, in a unique mating spatialposition (or indeed to another structure in a known fixed relationshipto the model 603) remote from parts of the model 603 representing dentalsurfaces, and thus facilitates the cementing procedure for the user asthere is a minimum or zero obfuscation of the chamber 665″ and analog230′ by the jig.

The physical model 603 according to this example can be made havinguniform hardness, for example as disclosed herein for physical model600, mutatis mutandis, or can be formed as a composite physical model,for example as disclosed below for composite physical model 800, mutatismutandis.

It is to be noted that the first subsystem 260 in which virtual modelsare created and operated on according to any of the examples of thepresently disclosed subject matter does not necessarily need to belocated in the same geographical location as the scanner 250 andpatient. Thus, while the scanning of the patient is usually done at adental clinic by the dentist or other dental practitioner, the dentalclinic can instead or additionally be linked to one or more dental labs,and possibly also to a dental service center via a communication systemor network such as for example the Internet or other suitablecommunications medium such as an intranet, local access network, publicswitched telephone network, cable network, satellite communicationsystem, and the like. Additionally or alternatively, the communicationsystem can include postal or courier services, the data beingcommunicated via a transportable medium such as an optical disc,magnetic disc and so on. In any case, once the virtual model is created,the physical dental model, and other dental procedures not carried outon the actual patient, can be carried out by the dental lab whichreceives the required data generated by the method 400 via thecommunications system. Additionally or alternatively, the physicaldental model can be manufactured in one location, and sent to anotherlocation in which the analog is implanted in the physical dental model.

Referring to FIG. 13, an example of method 900 for providing a compositephysical model of a dental structure according to the second aspect ofthe presently disclosed subject matter broadly includes the followingsteps 920 and 950:

-   -   Step 920—providing a virtual model of the physical dental        structure;    -   Step 950—using said virtual model, manufacturing a composite        physical model corresponding to said virtual model, the physical        model including a first physical model part and a second        physical model part having at least one physical property        different from a physical property of said first physical model        part.

In the following example, the dental structure is the aforesaid dentalstructure 100 which includes a dental implant 240 implanted therein at aparticular implant site 150, and includes hard dental surfaces 110 andsoft dental surfaces 120 thereof. Thus step 920 can correspond to step420 according to the first aspect of the presently disclosed subjectmatter, mutatis mutandis, wherein virtual model 500 of the dentalstructure 100 is generated. However, it is to be noted that method 900is not limited to such a dental structure, and can thus also beapplicable be applicable for the manufacture of other dental physicalcomposite models in a similar manner to that disclosed herein, mutatismutandis, whether configured for having an analog installed therein inany suitable manner, or whether the physical composite model is notconfigured for incorporating an analog—for example a regular dentalmodel, or one used for manufacturing and fitting a prosthesis on apreparation.

In other words, the method 900 is also applicable, mutatis mutandis, toother dental structures having hard dental structures (for exampleoptionally including a tooth preparation) and soft dental structures,and optionally having an absence of any implants in the dentalstructure. For example, where the dental structure lacks a dentalimplant, step 920 can be similar to step 420, but can exclude anyactivity directed to determining the spatial disposition of the implant,mutatis mutandis, and similarly step 950 excludes manufacturing ananalog installation structure, mutatis mutandis.

Referring to FIG. 13(a), and to FIGS. 14(a) to 14(c), step 950 caninclude the following substeps:

-   -   Step 952—identifying at least some virtual surfaces of virtual        model 500 corresponding to some or all of the soft dental        surfaces 120 of the dental structure 100;    -   Step 954—modifying virtual model 500 to create a virtual soft        model part 580 corresponding to at least some of the soft dental        surfaces 120, and a virtual hard model part 560 corresponding to        at least some of the hard dental surfaces 110.

In step 952, a zone or surface 910 is defined on the second virtualportions 508, around the virtual coronal opening 503 corresponding tothe zone of soft dental surfaces 120 of the original dental structure100 that surrounds the implant site 150 and that is to be represented inthe composite model 800 by the soft model part. For example, surface 910can extend up to the virtual gingival margins 915 of the virtual teeth917 (of the virtual portions 509) that are adjacent the virtual coronalopening 503.

The particular second virtual portions 508 can be identified by, andsurface 910 can be defined by, the user, in an interactive manner usingthe first subsystem 260 of system 200 (FIG. 3), for example.Alternatively, second virtual portions 508 can be identified and/orsurface 910 can be defined in an automated or semi-automated manner. Forexample, the computer system 260 can be programmed to automaticallyidentify the virtual coronal opening 503 and then identify and definesurface 910 by radiating outwardly along the second virtual portions 508of the virtual model 500 by a fixed spacing, for example, or until thecurvature of the virtual model 500 indicates that the surface is curvingin an upward direction, which is indicative of the first virtualportions 509.

It is evident that for at least this particular application of method900, it is only desired for a relatively small area around the implantsite 150 to be reproduced in the composite model 800 using a relativelysoft material, while the remainder of the composite model 800, includingother parts thereof that correspond to other soft dental surfaces 120,may be included in the hard model part. In other applications of method900, other parts or all of the parts of the virtual model 500 thatrepresent the soft dental surfaces 120 may be included in the soft modelpart.

In step 954, once surface 910 is defined, a second virtual surface 1420is defined, for example by displacing a copy of surface 910 in aninwardly or apical direction by a predefined displacement “d”. Forexample, displacement “d” can correspond to spacing between the mostcoronal part of surface 910 and the position of third virtual portion502 (corresponding to the position of the exposed part of prosthesisengaging part 248), or may be some percentage greater than this spacing,for example 105%, 110%, 125, 150% or 200% or more of this spacing. Then,an additional outer lateral virtual surface 930 is defined, joiningtogether the outer edges 911 and 921 of surfaces 910 and 1420,respectively, and where necessary an additional inner lateral virtualsurface 940 is defined, joining together the inner edges 912 and 922 ofsurfaces 910 and 1420, respectively.

Alternatively, second surface 1420 can be defined in any other suitablemanner—for example by defining a plane (or any other surface, e.g. apart-cylindrical surface) at a desired orientation (for example parallelto the occlusal plane or to any other suitable reference plane),displacing this plane in an apical direction AP from the position ofportion 502 by a suitable displacement or maintaining the plane atportion 502, and then intersecting the plane with second virtualportions 508, for example.

The virtual hard model part 560 is then created by removing surface 910and inner lateral virtual surface 940 from the virtual model 500, andadding surface 1420 and outer lateral virtual surface 930. The virtualhard model part 560 corresponds to the hard model part 860 of thecomposite physical model 800 that is to be manufactured.

A virtual soft model part 580, separate from the virtual hard model part560, is also created by joining surface 910 and inner lateral virtualsurface 940 to surface 1420 and outer lateral virtual surface 930, andthe virtual soft model part 580 corresponds to the soft model part 880of the physical composite model 800. In at least some variations of thisexample, a small spacing may be desired between the soft model part 880and the hard model part 860, for example for introducing an adhesivetherebetween, and in such cases the virtual soft model part 580 or thevirtual hard model part 560 is correspondingly modified by displacementof the corresponding surface 1420 thereof.

Referring again to FIG. 13(a), step 950 can further include thefollowing substeps:

-   -   Step 956—generating machine instructions for manufacturing the        physical composite model 800 including physical soft model part        880 based on and corresponding to virtual soft model part 580        and a physical hard model part 860, based on and corresponding        to said virtual hard model part 560.    -   Step 958—using the machine instructions, manufacturing the        physical composite model 800.

In step 956 the virtual soft model part 580 and the virtual hard modelpart 560 (which optionally may be combined in to a single virtual modelwhile retaining their characteristics) are suitably operated on, forexample via subsystem 260, to provide suitable machine instructions toenable in step 958 computer controlled manufacture of the physicalcomposite model 800 (which in this particular application of method 900also includes the physical installation structure 690 corresponding tothe virtual analog installation structure 590), for example usingsubsystem 280 (FIG. 3).

The exact nature of the machine instructions will depend, inter alia, onthe type of computer controlled manufacture being used in step 958, forexample CNC machining or any type of rapid prototyping (for examplestereo lithography, printing, sintering, etc.), and can be carried outusing the second subsystem 280, for example.

In the example illustrated in FIGS. 14(b) and 14(c), the hard model part860 and the soft model part 880 are separately manufactured and thencoupled together. The hard model part 860 can be manufactured based onand corresponding to the virtual hard model part 560, in a similarmanner to that disclosed above for the manufacture of physical model 600based on virtual model 500, mutatis mutandis. Thus, for example, a CNCmaterial removal operation or procedure can be conducted on a suitablehard material blank, or a suitable rapid prototyping method can be used,or a combination of both, or any other suitable computer-controlledmanufacturing technique based on the virtual hard model part 560.

The soft model part 880 can be formed from suitable relatively softmaterial and can be manufactured based on and corresponding to thevirtual soft model part 580 using the corresponding machineinstructions, in a similar manner to that disclosed above for themanufacture of physical model 600 based on virtual model 500, mutatismutandis. Preferably, the soft material is similar in at least one oftexture, resilience, color and softness to the natural gums, but othermaterials which are non-rigid can also be suitable, or that are at leastsofter than the material of the hard model part, and/or have differentcolors to the natural gums. For example, the soft material can berubber, silicone, or any other soft tissue material used in the art tocreate composite dental models.

The soft model part 880 can be formed in a number of different ways,based on the virtual hard model part 560 and using the appropriatemachine instructions derived therefrom. For example, soft model part 880can be formed via a rapid prototyping manufacturing method, using asuitably soft material—for example using an Objet rapid prototypingmachine (for example as disclosed in website objet.com), and a suitablematerial, for example as marketed under “TANGO”, which can beselectively provided with different levels of rigidity. Alternatively,and depending on the actual hardness of the soft model part, a CNCmaterial removal operation or procedure can be conducted on a suitablesoft material blank, or any other suitable computer-controlledmanufacturing technique based on the virtual hard model part 560 andusing the appropriate machine instructions derived therefrom.

Alternatively, a mold can be manufactured (in the form of a negativephysical model), also based on the virtual soft model part 580, toprovide mold surfaces that are substantially complementary to theouter-facing surfaces of the required soft model part 880. The mold canbe manufactured using, for example via CNC material removal methods on ablank of suitable mold material and/or via a material additive process,for example a rapid prototyping manufacturing method, or any othersuitable manufacturing method, using a suitably mold material, and usingthe appropriate machine instructions derived based on the virtual softmodel part 580. The soft model part 880 can then be formed by casting orinjecting suitable soft material into the mold and allowing to set. Itis to be noted that the hard model part 860 can also be manufactured ina similar manner from a mold in the form of negative physical model thatis based on the virtual hard model part 560 and manufactured based onand corresponding to the virtual hard model part 560, and using theappropriate machine instructions derived based thereon.

Alternatively, the soft model part 880 can be produced any othersuitable computer-controlled manufacturing technique based on thevirtual soft model part 580 and suitable relatively soft materials.

Referring to FIG. 14(c), the soft model part 880 is affixed onto thehard model part 860 to complete the composite physical model 800.

The soft model part 880 can be affixed onto the hard model part 860 in anumber of different ways, for example via a mechanical arrangement,adhesives, welding and so on. For example, an interlocking mechanicalarrangement can be provided, which is first modeled in the virtual softmodel part 580 and/or the virtual hard model part 560.

For example, and as illustrated in FIGS. 14(b) and 14(c), in one suchinterlocking mechanical arrangement the soft model part 880 can beformed with a number of holes 885 that are configured for receivingcomplementary projections 865 formed on the hard model part 860 incorresponding locations, so that when thus received, the soft model part880 is in the correct relative spatial relationship with respect to thehard model part 860. For example, the projections and holes can beformed integrally with the soft model part 880 and hard model part 860,and the corresponding virtual soft model part 580 and virtual hard modelpart 560 are correspondingly modified to include virtual of projections585 and complementary virtual holes 565′, respectively, in step 954 orin step 956, prior to manufacture. The projections and holes may haveany cross-sectional shapes, so long as they are complementary to oneanother, and the projections may be formed as pins, tabs, and so on.

In alternative variations of this example, the holes can be formed onthe hard model part 860 and the projections in the soft model part 880,or there can be a combination of projections and holes formed on thehard model part 860 that are paired to complementary holes andprojections formed in the soft model part 880. Alternatively, holes canbe formed on the hard model part 860 and in the soft model part 880, inmutual registry, and a plurality of pins used to connect paired holes inthe hard model part 860 and the soft model part 880.

Alternatively, for example, suitable wells can be formed incorresponding parts of the soft model part 880 and hard model part 860,and suitable magnets placed in these wells so that the soft model part880 and hard model part 860 can be engaged magnetically; the wells arefirst modeled in the corresponding virtual soft model part 580 andvirtual hard model part 560.

Alternatively, for example, the soft model part 880 can be overlaid onhard model part 860, and affixed therein using spikes traversing thesoft model part 880 and penetrating the hard model part 860, forexample.

Alternatively, a suitable adhesive can be used for fixing the soft modelpart 880 on hard model part 860. In such a case, the soft model part 880and/or hard model part 860, can be formed with a small clearancetherebetween to allow room for the adhesive, and this clearance is firstmodeled in the virtual soft model part 580 and/or the virtual hard modelpart 560.

Alternatively, any other suitable means can be used for affixing thesoft model part 880 to the hard model part 860, and modeled asappropriate in the virtual soft model part 580 and/or the virtual hardmodel part 560.

In any case, where appropriate, the virtual hard model part 560 and thevirtual soft model part 580, can be formed with spatial virtual featuresthat ensure that the corresponding physical features, formed on the hardmodel part 860 and the soft model part 880, respectively, provide (whenaligned) the correct spatial disposition between the hard model part 860and the soft model part 880. Such features may comprise suitablemarkings, for example.

Alternatively, in another example of steps 956 and 958, the compositephysical model 800 can be made by first manufacturing the hard modelpart 860, for example as disclosed above, mutatis mutandis, and then thesoft model part 880 can be subsequently formed in situ on the hard modelpart 860 of the composite physical model 800. For example, the virtualmodel 500 can be used to create a physical negative model of thecomposite physical model 800 to be used as a mold. The hard model part860 is mounted in the physical negative model, and this results in a gapbeing created inbetween these two components, the gap corresponding tothe soft model part 880. The soft model part 880 can then be formed bycasting or injecting suitable soft material into this gap via suitableinjection channels formed in the mold, for example, allowing the softmaterial to set as appropriate, and subsequently removing the physicalnegative model.

Alternatively, in another example of steps 956 and 958, a suitable rapidprototyping technique can be used for integrally forming the compositemodel 800, based on machine instructions derived from the virtual softmodel part 580 and/or the virtual hard model part 560. For example anObjet rapid prototyping machine (for example as disclosed in websiteobjet.com) can be used with two materials of different hardnesses, forexample as marketed under “TANGO”, which can be provided with differentlevels of rigidity. For parts of the composite physical model 800corresponding to the virtual hard model part 560, the rapid prototypingmachine uses a relatively hard material, while for parts of thecomposite physical model 800 corresponding to the virtual soft modelpart 580, the rapid prototyping machine uses a relatively soft material.

In at least this particular application of method 900 directed to thedental structure 100, and referring to FIG. 14(c), once the compositephysical model 800 is ready, the analog 230 can be inserted into thecomposite model 800 in a general coronal direction K in a similar mannerto that disclosed above for physical model 600, mutatis mutandis, toassume a spatial disposition P′ that is fixed in six degrees of freedomwith respect to the composite model 800, corresponding to the spatialdisposition P of the implant 240 with respect to the dental structure100. The prosthesis engaging part 238 of the analog 230 is thussurrounded by relatively soft material, for example in a similar mannerto the implant 240 in the dental structure 100. In the installedposition, the prosthesis engaging part 238 of the analog 230 is inabutment with the coronal opening 573′ of the composite model 800, andthus the exposed part of the prosthesis engaging part 238 is visible andaccessible via the coronal opening 573′.

In the above examples of implementation of method 900 with reference todental model 100, step 950 also includes manufacturing the correspondinganalog installation structure, as described herein with reference to thefirst aspect of the presently disclosed subject matter, mutatismutandis.

It is to be noted that the composite physical model 800 can be formedwith alignment features that allow the composite physical model 800 tobe aligned with a physical model of the opposite jaw to provide properocclusion, and/or be configured for mounting onto any dentalarticulator, in a similar manner to that described herein for physicalmodel 600, mutatis mutandis.

According to the first aspect of the presently disclosed subject matterthere is provided a system and method for manufacturing a physical modelof a physical dental structure that includes a dental implant.

According to the first aspect of the presently disclosed subject matterthere is also provided a method for creating a virtual model usable formaking a physical model of a physical dental structure that includes adental implant at an implant site, the method comprising:

using a computer system:

-   -   (a) receiving a virtual representation of dental surfaces of the        physical dental structure with dental implant data representing        a location and orientation of the dental implant with respect to        the dental surfaces;    -   (b) receiving a virtual analog structure, the virtual analog        structure being based on said dental implant; and    -   (c) creating the virtual model based on:        -   said virtual representation of dental surfaces; and        -   a virtual analog socket structure based on said virtual            analog structure and said dental implant data, and having an            virtual analog insertion opening that is spaced from parts            of the virtual model corresponding to dental surfaces and            the implant site.

The above method for creating a virtual model usable for making aphysical model of a physical dental structure that includes a dentalimplant at an implant site, can optionally comprise one or more of thefollowing features, in any desired combination or permutation:

-   -   (A) For example, said virtual analog structure is representative        of a desired dental analog that corresponds to the dental        implant, and wherein said virtual analog socket structure is        configured for virtually receiving therein said analog virtual        structure via said virtual analog insertion opening.    -   (B) Additionally or alternatively for example, said virtual        analog socket structure is configured for virtually receiving        therein said analog virtual structure at a virtual installed        position with respect to said virtual representation of dental        surfaces corresponding to said implant data.    -   (C) Additionally or alternatively for example, said virtual        analog insertion opening is at a location other than at said        virtual representation of dental surfaces.    -   (D) Additionally or alternatively for example, said virtual        analog insertion opening excludes a location in said virtual        representation of dental surfaces corresponding to a location of        the implant site in the physical dental structure.    -   (E) Additionally or alternatively for example, said virtual        analog insertion opening is different from an access opening to        the virtual analog socket structure that is located at a        location in said virtual representation of dental surfaces        corresponding to a location of the implant site in the physical        dental structure. For example, said access opening has a smaller        maximum width than a maximum width of said virtual analog        insertion opening.    -   (F) Additionally or alternatively for example, step (a) further        comprises receiving an auxiliary virtual representation of a        base structure having base surfaces unrepresentative of said        dental surfaces.    -   (G) Alternatively for example, step (a) further comprises        receiving an auxiliary virtual representation of a base        structure having base surfaces unrepresentative of said dental        surfaces, and for example, said virtual analog insertion opening        is at a location in said virtual representation of dental        surfaces corresponding to said base surface.    -   (H) Additionally or alternatively for example, said virtual        analog socket structure is configured for virtually receiving        therein said analog virtual structure via said virtual analog        insertion opening and along an insertion path, wherein said        insertion path is along an insertion direction including at        least one of:        -   a general coronal direction;        -   a non-apical direction;        -   a direction passing through said virtual representation of            dental surfaces from a first location with respect to the            virtual model corresponding to an inside of the dental            structure to a second location with respect to the virtual            model corresponding to an outside of the dental structure.    -   (I) Additionally or alternatively for example, step (a)        comprises scanning the dental structure to generate said virtual        representation of dental surfaces, and using a virtual implant        part in said virtual representation of dental surfaces        corresponding to an exposed part of the dental implant to obtain        said dental implant data. For example, step (a) comprises        comparing said virtual implant part to an implant virtual model        representative of the dental implant, and operating on said        virtual representation of dental surfaces to determine said        dental implant data based on a location and orientation of said        virtual implant part with respect to a remainder of said virtual        representation of dental surfaces.    -   (J) Alternatively, for example, step (a) comprises:        -   performing a first scanning procedure of said dental            structure with the dental implant exposed to generate said            virtual representation of dental surfaces;        -   mounting a scanning abutment to the dental implant in an            abutment spatial disposition with respect to the dental            implant, performing a second scanning procedure of said            dental structure including said scanning abutment to            generate an auxiliary virtual model, and using a virtual            scanning abutment part of the auxiliary virtual model            corresponding to the scanning abutment to obtain said dental            implant data.    -   (K) Additionally or alternatively for example, said virtual        analog installation structure comprises a virtual passageway        including said virtual analog insertion opening at one end        thereof and an auxiliary opening at an opposed end thereof, said        auxiliary opening corresponding to an interface between the        dental implant and exposed dental surfaces of the dental        structure in contact therewith. For example, said virtual        passageway is elongate defining a virtual passageway        longitudinal axis aligned with an insertion direction into said        virtual passageway. Additionally or alternatively for example,        said virtual passageway is formed comprising a virtual chamber        having a form generally complementary to an external form of at        least a part of the dental analog. Additionally or alternatively        for example, at least a part of said virtual passageway is        non-axisymmetric. Additionally or alternatively for example,        said virtual passageway comprises a virtual stop configured for        virtually abutting a corresponding part of said virtual analog        structure for limiting virtual penetration of the virtual analog        structure with respect to said virtual model. Additionally or        alternatively for example, a significant virtual clearance gap        is provided between said virtual passageway and said external        form of at least a part of the dental analog.    -   (L) Additionally or alternatively for example, said virtual        model is operated on to generate a virtual hard model part and a        virtual soft model part, wherein said virtual hard model part        corresponds to at least some hard tissues of the dental        structure and wherein said virtual soft model part corresponds        to at least some soft tissues of the dental structure. For        example, said virtual soft model part corresponds to an area of        the dental structure immediately adjacent the dental implant.    -   (M) Additionally or alternatively for example, the implant site        is defined as an area enclosed by a perimeter defined as the        interface between the dental surfaces and the dental implant.    -   (N) Additionally or alternatively for example, the method        further comprises:        -   generating machine instructions for manufacturing the            physical model based on said virtual model;        -   using the machine instructions, manufacturing the physical            model, the physical model comprising a physical analog            socket structure based on said virtual analog socket            structure.    -   (O) Said differently, there is provided a method for making a        physical model of a physical dental structure that includes a        dental implant at an implant site, the method comprising:        -   providing a virtual model as defined above optionally            including one or more of features (A) to (M) in any            combination or combination;        -   generating machine instructions for manufacturing a physical            model based on said virtual model; using the machine            instructions, manufacturing the physical model, the physical            model comprising a physical analog socket structure based on            said virtual analog socket structure.    -   (P) For example, said physical model is manufactured using one        of a computer controlled material removal process and a computer        controlled material additive process. For example: said computer        controlled material removal process can be a CNC machining        process; said computer controlled material additive process can        be a rapid prototyping process.    -   (Q) For example, said physical model is manufactured having a        substantially uniform hardness.    -   (R) Alternatively, for example, the physical model is        manufactured having a hard model part and a soft model part. For        example, said soft model part includes an area of said physical        model immediately adjacent a opening thereof corresponding to        said implant site and configured for exposing therethrough a        prosthesis system engaging end of said dental analog when said        dental analog is installed in the physical model. Additionally        or alternatively for example, said soft model part corresponds        to at least some soft tissues of said dental structure.        Additionally or alternatively for example, said hard model part        corresponds to at least some hard dental surfaces of said dental        structure.    -   (S) For example, prior to manufacturing said physical model,        said hard model part and said soft model part are first defined        in said virtual model as a corresponding virtual hard model part        and a corresponding virtual soft model part.    -   (T) Additionally or alternatively for example, the method for        making a physical model of a physical dental structure that        includes a dental implant at an implant site optionally further        comprises:        -   providing the dental analog; and        -   inserting the dental analog into said physical model via            said physical analog socket structure.    -   (U) A physical model, manufactured according to the method for        making a physical model of a physical dental structure that        includes a dental implant at an implant site    -   (V) A kit comprising a physical model as defined above and at        least one dental analog configured for use therewith by        insertion into the physical model via said physical analog        socket structure.

According to the first aspect of the presently disclosed subject matterthere is also provided a method for creating a virtual model usable formaking a physical model of a physical dental structure that includes adental implant, the method comprising:

using a computer system:

-   -   (a) receiving a virtual representation of dental surfaces of the        physical dental structure with dental implant data representing        a location and orientation of the dental implant with respect to        the dental surfaces, said dental surfaces including occlusal        facing dental surfaces and adjacent dental side surfaces;    -   (b) receiving a virtual analog structure, the virtual analog        structure being based on said dental implant; and    -   (c) creating the virtual model based on:        -   said virtual representation of dental surfaces; and        -   a virtual socket analog structure based on said virtual            analog structure and said dental implant data, and having a            virtual analog insertion opening at a location in said            virtual representation of dental surfaces corresponding to            said adjacent dental side surfaces of the dental surfaces.

For example, said adjacent dental side surfaces of the dental surfacescorrespond to gingival tissues of the dental structure, and/or, saidadjacent dental side surfaces of the dental surfaces correspond to toothor prosthetic surfaces of the dental structure. Additionally oralternatively the method for creating a virtual model usable for makinga physical model of a physical dental structure that includes a dentalimplant according to this aspect of the presently disclosed subjectmatter can optionally comprise one or more of features (A) to (F) and/or(H) to (V), mutatis mutandis, in any desired combination or permutation.

According to the first aspect of the presently disclosed subject matterthere is also provided a method for creating a virtual model usable formaking a physical model of a physical dental structure that includes adental implant at an implant site, the method comprising:

using a computer system:

-   -   (a) receiving a virtual representation of dental surfaces of the        physical dental structure with dental implant data representing        a location and orientation of the dental implant with respect to        the dental surfaces;    -   (b) receiving a virtual analog structure, the virtual analog        structure being based on said dental implant; and    -   (c) creating the virtual model based on:        -   said first virtual representation of dental surfaces; and        -   a virtual analog socket structure based on said virtual            analog structure and said dental implant data, said virtual            analog socket structure having a virtual analog insertion            opening and an access opening at a location corresponding to            the implant site, said access opening being different from            said virtual analog insertion opening, wherein said access            opening has a smaller maximum width than a maximum width of            said virtual analog insertion opening.

For example, the virtual analog insertion opening is spaced from partsof the virtual model corresponding to dental surfaces and the implantsite. Additionally or alternatively the method for creating a virtualmodel usable for making a physical model of a physical dental structurethat includes a dental implant according to this aspect of the presentlydisclosed subject matter can optionally comprise one or more of features(A) to (D) and/or (F) to (V), mutatis mutandis, in any desiredcombination or permutation.

According to this aspect of the presently disclosed subject matter thereis also provided a method for manufacturing a physical model of aphysical dental structure that includes dental surfaces and a dentalimplant at an implant site, for use with a dental analog correspondingto the dental implant, the method comprising:

-   -   receiving a virtual model of the physical dental structure and a        virtual analog installation structure in association with said        virtual model, said virtual analog installation structure being        based on the dental analog;    -   using said virtual model, manufacturing a physical model        corresponding to said virtual model, the physical model being        provided with an analog installation structure based on said        virtual analog installation structure and thereby configured for        enabling the dental analog to be inserted into said physical        model through an insertion opening,    -   wherein said insertion opening is spaced from a location in the        physical model corresponding to the implant site in the physical        dental structure.

The method optionally further comprises:

-   -   providing the dental analog; and    -   inserting said dental analog into said physical model via said        analog installation structure, and fixing said dental analog        therein at said analog spatial disposition.

Additionally or alternatively, for example, step (a) comprises scanningthe dental structure to generate said virtual representation of dentalsurfaces, and using a virtual implant part in said virtualrepresentation of dental surfaces corresponding to an exposed part ofthe dental implant to obtain said dental implant data. For example, step(a) comprises comparing said virtual implant part to an implant virtualmodel representative of the dental implant, and operating on saidvirtual representation of dental surfaces to determine said dentalimplant data based on a location and orientation of said virtual implantpart with respect to a remainder of said virtual representation ofdental surfaces.

Alternatively, for example, step (a) comprises:

-   -   performing a first scanning procedure of said dental structure        with the dental implant exposed to generate said virtual        representation of dental surfaces;    -   mounting a scanning abutment to the dental implant in an        abutment spatial disposition with respect to the dental implant,        performing a second scanning procedure of said dental structure        including said scanning abutment to generate an auxiliary        virtual model, and using a virtual scanning abutment part of the        auxiliary virtual model corresponding to the scanning abutment        to obtain said dental implant data.

Additionally or alternatively, for example, said virtual model comprisesa virtual external surface corresponding to dental surfaces of saiddental structure, and further comprising modifying said virtual model toinclude a virtual model base comprising a respective virtual externalbase surface. For example, said virtual external base surface excludesany representation of said dental surfaces of said dental structure.Additionally or alternatively, for example, in step (b) said analoginstallation structure is first defined in said virtual model as avirtual analog installation structure, said virtual analog installationstructure comprising a virtual passageway having a first virtual openingprovided in said virtual model base, and a second virtual openingcorresponding to an interface between said dental implant and exposeddental tissues of said dental structure in contact therewith. Forexample, said virtual passageway is elongate defining a virtualpassageway longitudinal axis aligned with said general coronaldirection. Additionally or alternatively, for example, said virtualpassageway is formed comprising a virtual chamber having a formgenerally complementary to an external form of at least a coronal partof said dental analog, such that a physical chamber corresponding tosaid virtual chamber and formed in said physical model provides a closefit with respect to at least said coronal part of said dental analog toaccommodate said dental analog at said analog spatial disposition withrespect to the physical model. Additionally or alternatively, forexample, at least a part of said virtual passageway is non-axisymmetric.Additionally or alternatively, for example, said virtual passagewaycomprises a virtual stop corresponding to a mechanical stop in saidphysical model configured for limiting penetration of the dental analogto said installed position. Additionally or alternatively, for example,step (b) comprises aligning the virtual analog installation structurewith said virtual model based on said virtual implant spatialdisposition to ensure that said analog installation structure allowssaid analog to attain said analog spatial disposition in the physicalmodel. Additionally or alternatively, for example, said virtualpassageway is formed comprising a virtual chamber having a formgenerally complementary to an external form of at least a coronal partof the dental analog, such that said chamber formed in said physicalmodel provides a significant clearance gap with respect to said dentalanalog, wherein said dental analog comprises a jacket formed of suitablemodel material, said jacket having an external form substantiallycomplementary to that of said chamber, to enable a composite analogcomprising said dental analog including said jacket to be accommodatedin said chamber at said analog spatial disposition.

Additionally or alternatively, for example, said virtual passagewaycomprises a virtual chamber having a form generally complementary to anexternal form of at least a coronal part of said dental analog, suchthat said chamber formed in said physical model provides a significantclearance gap with respect to said dental analog, and furthercomprising:

-   -   maintaining said analog spatial disposition between said dental        analog and said chamber using a jig at least until the dental        analog is affixed therein;    -   introducing a suitable filler into said clearance gap to fix        said dental analog in said chamber at said analog spatial        disposition.

Additionally or alternatively, for example, said insertion opening is ata location other than at physical model dental surfaces corresponding tosaid dental surfaces.

Additionally or alternatively, for example, said insertion openingexcludes a location in said physical model corresponding to a locationof the implant site in the dental structure.

Additionally or alternatively, for example, said insertion opening isdifferent from an access opening to the analog installation structurethat is located at a location in said physical model corresponding to alocation of the implant site in the physical dental structure. Forexample, said access opening has a smaller maximum width than a maximumwidth of said insertion opening.

Additionally or alternatively, for example, herein said insertion pathis along an insertion direction is at least one of:

-   -   a general coronal direction; a non-apical direction;    -   a direction passing through a representation of said dental        surfaces in the physical model, from a first location inside the        physical model to a second location outside of the physical        model.

Additionally or alternatively, for example, step (b) comprises:

-   -   generating machine instructions for manufacturing the physical        model based on said virtual model and the virtual analog        installation structure;    -   using the machine instructions, manufacturing the physical        model.

Additionally or alternatively, for example, step (b) wherein saidphysical model is manufactured using one of a computer controlledmaterial removal process and a computer controlled material additiveprocess. For example: said computer controlled material removal processcan be a CNC machining process; said computer controlled materialadditive process can be a rapid prototyping process.

Additionally or alternatively, for example, said physical model ismanufactured having a substantially uniform hardness.

Alternatively, for example, the physical model is manufactured having ahard model part and a soft model part. For example, said soft model partincludes an area of said physical model immediately adjacent a coronalopening thereof configured for exposing therethrough a coronal end ofsaid dental analog when installed in the physical model. Additionally oralternatively, for example, said soft model part corresponds to at leastsome soft tissues of said dental structure. Additionally oralternatively, for example, said hard model part corresponds to at leastsome hard dental surfaces of said dental structure. Additionally oralternatively, for example, prior to manufacturing said physical model,said hard model part and said soft model part are first defined in saidvirtual model as a corresponding virtual hard model part and acorresponding virtual soft model part.

According to this aspect of the presently disclosed subject matter thereis also provided a physical model, manufactured according to the methodfor making a physical model of a physical dental structure that includesa dental implant at an implant site

According to this aspect of the presently disclosed subject matter thereis also provided a kit comprising a physical model as defined above andat least one dental analog configured for use therewith by insertioninto the physical model via said physical analog socket structure.

According to this aspect of the presently disclosed subject matter thereis also provided a physical model of a dental structure, the dentalstructure including a dental implant at an implant site, the physicalmodel being configured for enabling insertion therein of a dental analogcorresponding to the dental implant via an insertion opening that isspaced from a model implant site location on the physical modelcorresponding to the implant site.

For example, the physical model is configured for enabling insertiontherein of the dental analog to an installed position in a mannerensuring that a surface topology of said physical model in proximity tothe dental analog in the installed position remain representative of therespective surface topology of the dental structure in the vicinity ofthe dental implant at least during said insertion. Additionally oralternatively, for example, the physical model comprises an analoginstallation structure configured for enabling the dental analog to beinserted therein via said insertion opening to said installed positiontherein having an analog spatial disposition with respect to saidphysical model corresponding to a physical implant spatial dispositionof the dental implant with respect to the dental structure.

According to this aspect of the presently disclosed subject matter thereis also provided a said physical model comprises an external surfacecorresponding to dental surfaces of the dental structure, and furthercomprises a model base comprising a respective external base surface.For example, said external base surface excludes any representation ofthe dental surfaces of the dental structure. Additionally oralternatively, for example, said analog installation structurecomprising a passageway extending from said insertion opening providedin said model base, and a second opening on said external surface atsaid model implant site location. For example, said passageway iselongate defining a passageway longitudinal axis aligned with a generalcoronal direction. For example, said passageway longitudinal axis isco-axial with a longitudinal axis of the dental analog when the dentalanalog is in said installed position. Additionally or alternatively, forexample, said passageway comprises a chamber having a form generallycomplementary to an external form of at least a coronal part of thedental analog, such that said physical chamber provides a close fit withrespect to at least said coronal part of the dental analog toaccommodate the dental analog at said analog spatial disposition withrespect to the physical model. Additionally or alternatively, forexample, said passageway comprises a chamber having a form generallycomplementary to an external form of at least a coronal part of saiddental analog, such that said chamber formed provides a significantclearance gap with respect to said dental analog. Additionally oralternatively, for example, at least a part of said passageway isnon-axisymmetric. Additionally or alternatively, for example, saidpassageway comprises a mechanical stop configured for limitingpenetration of the dental analog to said installed position.

Additionally or alternatively, for example, said physical modelcomprises a uniform hardness.

Alternatively, for example, the physical model comprises a hard modelpart and a soft model part. For example, said soft model part includesan area of said physical model adjacent a second opening thereofconfigured for exposing therethrough a coronal end of said dental analogwhen installed in the physical model. Additionally or alternatively, forexample, said soft model part corresponds to at least some soft tissuesof the dental structure. Additionally or alternatively, for example,said hard model part corresponds to at least some hard dental surfacesof the dental structure.

Additionally or alternatively, for example, the implant site correspondsto an interface between the dental implant and exposed dental tissues ofthe dental structure in contact therewith

Additionally or alternatively, for example, said second opening has asmaller maximum width than a maximum width of said insertion opening.According to this aspect of the presently disclosed subject matter thereis also provided a dental analog configured for being inserted into apassageway of a physical model of a dental structure, which dentalstructure includes a dental implant at an implant site, the passagewayincluding an insertion opening and a second opening corresponding to theimplant site, said second opening having a smaller maximum width than amaximum width of said insertion opening. For example, the dental analogcomprises a first analog end corresponding to said insertion opening anda second analog end corresponding to said second opening, wherein saidsecond analog end has a smaller maximum width than a maximum width ofsaid first analog end.

Additionally or alternatively, for example, the dental analog has acoronal portion and an enlarged apical portion, wherein in use saiddental analog is implanted in a physical model of a dental structure inan installed position such that said coronal portion and said enlargedapical portion are within the physical model.

Additionally or alternatively, for example, the dental analog comprisesa longitudinal axis, and wherein at least a longitudinal portion of oneof said coronal portion and an apical portion is non-axisymmetric aboutsaid longitudinal axis.

Additionally or alternatively, for example, the dental analog comprisesan external form configured for being inserted into the physical dentalmodel in a general coronal direction to the installed position via thepassageway formed in the physical model, wherein at least a portion ofsaid external form is non-axisymmetric with respect to said generalcoronal direction. For example, at least one of said coronal portion andsaid apical portion is configured for fixing a spatial disposition ofthe dental analog with respect to the passageway in up to four degreesof freedom associated with axes orthogonal to the general coronaldirection.

Additionally or alternatively, for example, said enlarged apical portionacts as a mechanical stop with respect to a corresponding part of thepassageway to define the longitudinal position of said dental analogwith respect to the passageway.

Additionally or alternatively, for example, said dental analog comprisesa prosthesis interface analog part and a prosthesis engaging analog partrespectively corresponding to a prosthesis interface implant part andprosthesis engaging implant part of respective dental implant, whereinthe dental implant is chosen from a plurality of dental implantconfigurations having different configurations for the respective saidprosthesis interface implant part and said prosthesis engaging implantpart.

According to this aspect of the presently disclosed subject matter thereis also provided a kit comprising a physical model of a dental structurethat includes a dental implant at an implant site, the physical modelhaving a passageway, an insertion opening and a second openingcorresponding to the implant site, said second opening smaller maximumwidth than a maximum width of said insertion opening and at least onedental analog as defined above.

According to the first aspect of the presently disclosed subject matterthere is also provided a system and method for manufacturing a physicalmodel of a dental structure that includes a dental implant. In at leastone example, the physical model is configured to allow a dental analogcan be inserted into the physical model in a general coronal direction.A virtual model of the dental structure is provided including a virtualimplant spatial disposition with respect to the virtual modelcorresponding to a physical implant spatial disposition of the dentalimplant with respect to the physical dental structure. A virtual analoginstallation structure is defined in the virtual model. Using thevirtual model, a physical model corresponding to the virtual model ismanufactured, the physical model being provided with a physical analoginstallation structure corresponding to the virtual analog installationstructure. The physical analog installation structure is configured forenabling a dental analog, corresponding to the dental implant, to beinserted in a general coronal direction with respect to the physicalmodel to an installed position in the physical model. In the installedposition, the dental analog has an analog spatial disposition withrespect to the physical model corresponding to the physical implantspatial disposition of the dental implant with respect to the physicaldental structure.

According to the second aspect of the presently disclosed subject matterthere is provided a system and method for manufacturing a compositephysical dental model of a dental structure, the method broadlycomprising:

-   -   (a) providing a virtual model of the dental structure;    -   (b) using said virtual model, manufacturing a composite physical        model corresponding to said virtual model, the physical model        including a first model part and a second model part having at        least one physical property different from a physical property        of said first model part, wherein said first model part and said        second model part are previously defined in said virtual model,        and wherein said at least one physical property excludes a        surface topology.

For example said physical property is a mechanical property.

For example, step (b) comprises:

-   -   (b1) identifying at least some virtual surfaces of said virtual        model corresponding to at least a part of the soft dental        surfaces of the dental structure;    -   (b2) modifying said virtual model to create a first virtual        model part corresponding to said at least part of the soft        dental surfaces, and a second virtual model part corresponding        to at least a part of the hard dental surfaces of the dental        structure.

For example, step (b) further comprises:

-   -   (b3) generating machine instructions for manufacturing the        physical composite model including said first model part based        on and corresponding to said first virtual model part and said        second model part based on and corresponding to said second        virtual model part;    -   (b4) using the machine instructions, manufacturing the physical        composite model.

Additionally or alternatively, said virtual model comprises a virtualsurface corresponding to a dental surface of said dental structure,wherein said first virtual model part includes a first virtual surfacepart of said virtual surface and wherein said second virtual model partincludes a second virtual surface part of said virtual surface. Forexample, said first virtual surface part is in virtual abutment withsaid second virtual surface part.

Additionally or alternatively, in step (b4), said first model part isproduced separately from said second model part, and wherein said firstmodel part and model part are joined together in said composite model.For example, said second physical model part is produced using one of acomputer controlled material removal process and a computer controlledmaterial additive process: for example, the computer controlled materialremoval process is a CNC machining process; for example the computercontrolled material additive process is a rapid prototyping procedure.For example, said first physical model part is produced by a separatecasting procedure or via a rapid prototyping procedure.

For example, said first physical model part and said second physicalmodel part are produced with affixing features configured for enablingthe first physical model part to be affixed with respect to the secondphysical model part in a relative spatial disposition therewithcorresponding to the relative spatial disposition of the respective realparts of the real dental structure. For example, said affixing featurescorrespond to virtual affixing features previously defined in said firstvirtual model part and said second virtual model part in step (b).

Alternatively, in step (b4), said second model part is produced first,and said first model part is produced in situ on said second model part.For example, said second physical model part is produced using one of acomputer controlled material removal process and a computer controlledmaterial additive process, and wherein said first physical model part isproduced by a casting procedure

Alternatively, in step (b4), said first model part is producedintegrally with said second model part. For example, said first modelpart and said second model part are integrally produced via a computercontrolled material additive process, for example a rapid prototypingprocedure. For example, said rapid prototyping procedure employs a firstmaterial for producing said first model part, and a second material forproducing said second model part, said first material and said secondmaterial being of a different said property one from another. Forexample, said first material is relatively softer than said secondmaterial.

Additionally or alternatively, said at least one physical property ischosen from texture, resilience, color and softness. Additionally oralternatively, said composite model is further configured with alignmentfeatures for enabling occlusal alignment of the composite physical modelwith a physical dental model of an opposite jaw.

Additionally or alternatively, the dental structure includes a dentalimplant, and wherein said composite model is configured for installingtherein a corresponding dental analog. For example, said first modelpart includes an area of said composite model adjacent a coronal openingthereof configured for exposing therethrough a coronal end of the dentalanalog when installed in the composite model. For example such acomposite model can further assist a dental technician in the designand/or preparation of the permanent abutment, coping, prosthesis and soon.

A composite physical dental model is also provided, produced with therespective method as defined above.

According to this aspect of the presently disclosed subject matter,before manufacturing the composite model, the soft model part and thehard model part are defined as virtual models.

In the method claims that follow, alphanumeric characters and Romannumerals used to designate claim steps are provided for convenience onlyand do not imply any particular order of performing the steps.

Finally, it should be noted that the word “comprising” as usedthroughout the appended claims is to be interpreted to mean “includingbut not limited to”.

While there has been shown and disclosed example examples in accordancewith the presently disclosed subject matter, it will be appreciated thatmany changes can be made therein without departing from the spirit ofthe presently disclosed subject matter.

What is claimed is:
 1. A method for creating a virtual dental model of adental structure of a patient for a restorative procedure, the methodcomprising: generating a virtual model of the dental structure of thepatient, the virtual model including a portion associated with softdental surfaces, a portion associated with hard dental surfaces, and animplant site; identifying a first portion of the virtual modelcorresponding to a portion of the soft dental surfaces within theimplant site, the first portion having a first virtual surfacecorresponding to a surface of the soft dental surfaces; defining asecond virtual surface displaced in an apical direction from the firstvirtual surface; defining a first lateral virtual surface that extendsbetween at least the first virtual surface and the second virtualsurface; modifying the virtual model to create: a first virtual modelpart having surfaces corresponding to the first virtual surface, thesecond virtual surface, and the first lateral virtual surface and asecond virtual model part corresponding to at least a portion of thehard dental surfaces of the virtual model and having a third virtualsurface that corresponds to the second virtual surface, at least aportion of the second virtual model part being in a coronal directionwith respect to the first virtual model part; and outputting a compositemodel corresponding to the modified virtual model, the composite modelincluding a first model part and a second model part, the first modelpart corresponding to a shape of the first virtual model part and thesecond model part corresponding to a shape of the second virtual modelpart.
 2. The method of claim 1, wherein the implant site of the virtualmodel comprises a surface corresponding to an analog interface.
 3. Themethod of claim 1, wherein the implant site of the virtual modelcomprises a surface corresponding to an abutment.
 4. The method of claim1, wherein the first virtual model part is bounded by the first virtualsurface, the second virtual surface, and the first lateral virtualsurface.
 5. The method of claim 1, wherein the first lateral virtualsurface is joined to the first virtual surface at a first edge and tothe second virtual surface at a second edge.
 6. The method of claim 1,wherein the second virtual surface is a planar surface.
 7. The method ofclaim 1, further comprising a second lateral virtual surface of thefirst virtual model part, that extends between at least the firstvirtual surface and the second virtual surface and is displacedlaterally from the first lateral virtual surface.
 8. The method of claim1, wherein outputting the composite model comprises outputtinginstructions for manufacturing a physical composite model based on themodified virtual model.
 9. The method of claim 1, wherein the secondvirtual model part and the first virtual model part virtually abut eachother at the second virtual surface and the third virtual surface. 10.The method of claim 1, wherein the third virtual surface is displaced inan apical direction from the second virtual surface.
 11. A system forcreating a virtual dental model of a dental structure of a patient for arestorative procedure, the system comprising: a computer systemincluding a processor and memory programmed to cause the computer systemto: generate a virtual model of the dental structure of the patient, thevirtual model including a portion associated with soft dental surfaces,a portion associated with hard dental surfaces, and an implant site;identify a first portion of the virtual model corresponding to a portionof the soft dental surfaces within the implant site, the first portionhaving a first virtual surface corresponding to a surface of the softdental surfaces; define a second virtual surface displaced in an apicaldirection from the first virtual surface; define a first lateral virtualsurface that extends between at least the first virtual surface and thesecond virtual surface; modify the virtual model to create: a firstvirtual model part having surfaces corresponding to, the first virtualsurface, the second virtual surface, and the first lateral virtualsurface that define a shape of the first virtual model part, and asecond virtual model part corresponding to at least a portion of thehard dental surfaces of the virtual model and having a third virtualsurface that corresponds to the second virtual surface, at least aportion of the second virtual model part being in a coronal directionwith respect to the first virtual model part; and output a compositemodel corresponding to the modified virtual model, the composite modelincluding a first model part and a second model part, the first modelpart corresponding to the shape of the first virtual model part and thesecond model part corresponding a shape of the second virtual modelpart.
 12. The system of claim 11, wherein the first virtual model partis bounded by the first virtual surface, the second virtual surface, andthe first lateral virtual surface.
 13. The system of claim 11, whereinthe first lateral virtual surface is joined to the first virtual surfaceat a first edge and to the second virtual surface at a second edge. 14.The system of claim 11, wherein the second virtual surface is a planarsurface.
 15. The system of claim 11, wherein the output of the compositemodel comprises instructions for manufacturing a physical compositemodel based on the modified virtual model.
 16. The system of claim 11,wherein the second virtual model part and the first virtual model partvirtually abut each other at the second virtual surface and the thirdvirtual surface.
 17. The system of claim 11, wherein the third virtualsurface is displaced in an apical direction from the second virtualsurface.